Kaiser Bottom Fish OnlineFree trialNew StuffHow It WorksContact UsTerms of UseHome
Specializing in Canadian Stocks
SearchAdvanced Search
Welcome Guest User   (more...)
Home / Education
Education
 

Sheahan Diamond Literature Reference Compilation 2015


The Sheahan Diamond Literature Reference Compilation
The Sheahan Diamond Literature Reference Compilation is compiled by Patricia Sheahan who publishes on a monthly basis a list of new scientific articles related to diamonds as well as media coverage and corporate announcementscalled the Sheahan Diamond Literature Service that is distributed as a free pdf to a list of followers. Pat has kindly agreed to allow her work to be made available as an online digital resource at Kaiser Research Online so that a broader community interested in diamonds and related geology can benefit. The references are for personal use information purposes only; when available a link is provided to an online location where the full article can be accessed or purchased directly. Reproduction of this compilation in part or in whole without permission from the Sheahan Diamond Literature Service is strictly prohibited. Return to Diamond Resource Center
Sheahan Diamond Literature Reference Compilation - Scientific Articles by Author for all years
A B-Bq Br+ C D E F G-Gq Gr+ H I J K-Km Kn+ L M-Md Me+ N O P Q R S-Sg Sh+ T U V W X Y Z
Sheahan Diamond Literature Reference Compilation - Media/Corporate References by Name for all years
A B C D-Di Di+ E F G H I J K L M N O P Q R S T U V W X Y Z
Tips for Users
Posted/Published Reference CodesThe SDLRC provides 3 types of references identified in the reference code. DS for scientific article, DM for a media article, and DC for a corporate announcement. Consider DS0512-0001. The DS stands for "diamond scientific". 05 stands for 2005, the year the reference was posted. 12 represents the month the reference was posted. For all years prior to 2015 the default month is 12. -0001 is the reference's identifier and it does not mean anything. The number below the refence code, ie 2015, is the year the article was published. Note that the posted year may sometimes be later than the published year.
Sort OrderReferences are sorted by the "author" name and when the reference was posted to the compilation.
Most RecentIf the reference code is highlighted yellow, the reference was made available through the most recent monthly compilation of new literature. Use this to check out new references. When new references are posted, we make it our priority to track down an online link and obtain an abstract. With regard to older references, tracking down an abstract and an online link is a work in progress.
Link to external location of article: If the title has a link, it means we have found a location online where you can either retrieve the full article free, or purchase access to it. The Sheahan Diamond Literature Service is not a technical article procurement service; if you want a restricted article, you must deal directly with the vendor who controls the copyright to the article.
Searching this page for a specific term or authorIn your Firefox browser click Edit in the menu bar and then Find. In the Find box that shows up at the bottom of the web page enter your search term. Firefox will highlight all occurrences. This is particularly helpful when the author you are seeking was not the lead author by whom the compilation is sorted.
Sending or sharing a referenceThe left column (Posted/Published) has an embedded hyperlink for each reference. In Firefox, if you right click on it, you can obtain the link url for that reference's location within the page, which you can copy and paste into an email or any other document. You can also use the "share this link" option to tweet, facebook etc the link.
Monthly Sheahan Diamond Newsletters for 2015
January 2015 May 2015 September 2015
February 2015 June 2015 October 2015
March 2015 July 2015 November 2015
April 2015 August 2015 December 2015
2015 Reference Compilation
Posted/
Published
AuthorTitleSourceRegionKeywords
DC1512-2413
2015
92 Resources Corporation92 Resources Corp. considers Finland diamond property, announces working capital private placement.92 Resources Corporation, Nov. 18, 1p.Europe, FinlandNews item - press release
DM1511-2110
2015
Abreu, F., Silva, L.F.How illegal diamond mining threatens Brazil's indigenous communities. Reported in Republicofmining.cominsightcrime.org, Oct. 14, 2p.South America, BrazilNews item - legal
DC1507-1379
2015
Adamera Minerals CorporationAdamera completes sale of diamond data.Adamera Minerals Corp., May 28, 1p.Canada, NunavutNews item - press release
DS1502-0036
2015
Afanasiev, V., Ashchekov, I., Nikolenko, E.Concentrates and mantle xenocrysts from the Lao River Guinea and reconstruction of the mantle structure. Economic Geology Research Institute 2015, Vol. 17,, # 2484, 1p. AbstractAfrica, GuineaKimberlite dykes
DC1502-1380
2015
Afri-Can Marine Minerals CorporationAfri-Can Marine Minerals Corporation trading halt and resignation of executives and directors. Afri-Can Marine Minerals Corporation, Jan. 5, 1p.Africa, NamibiaNews item - press release
DS1501-0001
2014
Ague, J.J.Deep carbon: subduction goes organic.Nature Geoscience, 2p.MantleCarbon

Abstract: Aqueous subduction-zone fluids contain CO2 and methane. New calculations indicate that these fluids also host a wide array of organic carbon species, in concentrations sufficient to influence the deep carbon cycle.
DS1511-1819
2014
Ahmat, A.L.The Ellendale diamond field: exploration history, discovery, geology and mining.Australian Gemmologist, Vol. 24, 12, pp. 280-288.AustraliaDeposit - Ellendale

Abstract: The Ellendale diamond field in West Kimberley is one of only three hard-rock diamond mine locations in Australia. Though not the first Australian diamond mine, Ellendale was the country’s first hard-rock deposit. It holds a special place in world diamond history as it led in November 1976 to the recognition of a new host-rock for diamond, olivine lamproite. Up until that time, commercial-sized diamonds were considered to be sourced only from kimberlite. The Ellendale lamproites are geologically very young, only 22 Ma (million of years) old. Within several years of the initial discovery, some 46 lamproite pipes were found at Ellendale. By 1980, 38 of these pipes had been assessed for their diamond content. More than two decades later, geologists from the Kimberley Diamond Company (KDC) recognized eluvial diamond enrichment over these pipes. After a lengthy legal battle, they wrested the Ellendale mining lease from the Ashton Joint Venture and commenced mining there in May 2002. Ellendale is recognized as a source of high-value fancy yellow diamonds. These high priced stones have been marketed through a special deal with Tiffany & Co since 2009. But the future of mining there is tenuous. Ellendale 4 was closed in 2009, and the high Australian dollar, combined with dwindling reserves, may jeopardize the survival of Ellendale 9.
DS1502-0037
2015
Ahmed, A.H., Habtoor, A.Heterogeneously depleted Precambrian lithosphere deduced from mantle peridotites and associated chromitite deposits of Al, Ays ophiolite, northwestern Arabian shield, Saudi Arabia.Ore Geology Reviews, Vol. 67, pp. 279-296.Africa, Saudi ArabiaPeridotite

Abstract: The mantle section of Al'Ays ophiolite consists of heterogeneously depleted harzburgites, dunites and large-sized chromitite pods. Two chromitite-bearing sites (Site1 and Site2), about 10 km apart horizontally from one another, were examined for their upper mantle rocks. Cr-spinels from the two sites have different chemistry; Cr-rich in Site1 and Al-rich in Site2. The average Cr-ratio = (Cr/(Cr + Al) atomic ratio) of Cr-spinels in harzburgites, dunites and chromitites is remarkably high 0.78, 0.77 and 0.87, respectively, in Site1, compared with those of Site2 which have intermediate ratio averages 0.5, 0.56 and 0.6, respectively. The platinum-group elements (PGE) in chromitites also show contrasting patterns from Site1 to Site2; having elevated IPGE (Os, Ir, Ru) and strongly depleted in PPGE (Rh, Pt, Pd) with steep negative slopes in the former, and gentle negative slopes in the latter. The oxygen fugacity (?log fO2) values deduced from harzburgites and dunites of Site1 show a wide variation under reducing conditions, mostly below the FMQ buffer. The Site2 harzburgites and dunites, on the other hand are mostly above the FMQ buffer. Two magmatic stages are suggested for the lithospheric evolution of Al'Ays ophiolite in response to a switch of tectonic setting. The first stage produced a peridotites–chromitites suite with Al-rich Cr-spinels, possibly beneath a mid-ocean ridge setting, or most likely in back-arc rift of a supra-subduction zone setting. The second stage involved higher degrees of partial melting, produced a peridotites–chromitites suite with Cr-rich Cr-spinels, possibly in a fore-arc setting. The coexistence of compositionally different mantle suites with different melting histories in a restricted area of an ophiolite complex may be attributable to a mechanically juxtaposed by mantle convection during recycling. The mantle harzburgites and dunites are apt to be compositionally modified during recycling process; being highly depleted (Site1 case) than their original composition (Site2 case).
DS1503-0131
2015
Alifirova, T.A., Pokhilenko, L.N., Korsakov, A.V.Apatite, SiO2, rutile and orthopyroxene precipitates in minerals of eclogite xenoliths from Yakutian kimberlites, Russia.Lithos, Vol. 226, pp. 31-49.Russia, YakutiaDeposit - Udachnaya, Zarnitsa, Obnazhennaya

Abstract: Eclogite mantle xenoliths from the central part of Siberian craton (Udachnaya and Zarnitsa kimberlite pipes) as well as from the northeastern edge of the craton (Obnazhennaya kimberlite) were studied in detail. Garnet and clinopyroxene show evident exsolution textures. Garnet comprises rutile, ilmenite, apatite, and quartz/coesite oriented inclusions. Clinopyroxene contains rutile (± ilmenite) and apatite precipitates. Granular inclusions of quartz in kyanite and garnet usually retain features of their high-pressure origin. According to thermobarometric calculations, studied eclogitic suite was equilibrated within lithospheric mantle at 3.2–4.9 GPa and 813–1080 °C. The precursor composition of garnets from Udachnaya and Zarnitsa eclogites suggests their stability at depths 210–260 km. Apatite precipitation in clinopyroxenes of Udachnaya and Zarnitsa allows us to declare that original pyroxenes could have been indicative of their high P–T stability. Raman spectroscopic study of quartz and coesite precipitates in garnet porphyroblasts confirms our hypothesis on the origin of the exsolution textures during pressure-temperature decrease. With respect to mineralogical data, we suppose the rocks to be subjected to stepwise decompression and cooling within mantle reservoir.
DM1501-0441
2014
AllAfricaMissing 100 carat diamond sold for US $ 1.5 million in Dubai. West African diamond company.Allafrica.com, Dec. 15, 1p.Africa, LiberiaNews item - legal
DM1501-2481
2014
AllAfricaBotswana: more in store for Jwaneng, Orapa mines.Allafrica.com, Nov. 30, 1p.Africa, BotswanaNews item - Debswana
DM1502-0442
2014
AllAfricaMwadui U.S. production, mine life span. Allafrica.com, Dec. 22, 1/2p.Africa, TanzaniaNews item - Petra
DM1502-0443
2014
AllAfricaEndiama to reduce operation costs.Allafrica.com, Dec. 30, 1/4p.Africa, AngolaNews item - Endiama
DM1502-0444
2014
AllAfricaGov't still fighting for diamonds seized in Belgium.Allafrica.com, Dec. 30, 1/4p.Africa, ZimbabweNews item - legal
DM1502-0445
2015
AllAfricaLunda Sul - Catoca ensures continued focus on betterment of working conditions.Allafrica.com, Jan. 5, 1/4p.Africa, AngolaNews item - Catoca
DM1502-0446
2015
AllAfricaIts time we became diamond people. ( value added processes needed)Allafrica.com, Jan. 10, 1p. Africa, ZimbabweNews item - legal
DM1502-0447
2015
AllAfricaFresh bid to grab mining companies…. Murowa mentioned.Allafrica.com, Jan. 17, 1/4p.Africa, ZimbabweNews item - Rio Tinto
DM1503-0448
2015
AllAfricaAngolan mining sector new project … Cambange in eastern Lunda Norte.Allafrica.com, Feb. 12, 1p.Africa, AngolaNews item - Mining UARi-society
DM1504-0452
2015
AllAfricaChinamasa - forget diamonds, Zim is broke.AllAfrica.com, Mar. 5, 1/2p.Africa, ZimbabweNews item - Marange
DM1504-0453
2015
AllAfricaBotswana: Debswana upgrades Seepapitso Labs.AllAfrica.com, Mar. 12, 1/2p.Africa, NamibiaNews item - Debswana
DM1504-0454
2015
AllAfricaDiamond board wants 24 hr access to Oranjemund.AllAfrica.com, Mar. 12, 1/2p.Africa, NamibiaNews item - legal
DM1505-0449
2015
AllAfricaProduction at Mwadui Diamond mine rises. 27% to 57,542 caratsAllafrica.com, Apr. 17, 1/4p.Africa, TanzaniaNews item - Petra
DM1505-2476
2015
AllAfricaDiamond miners on looting spree.Allafrica.com, Mar. 27, 1/4p.Africa, ZimbabweNews item - Marange
DM1507-0455
2015
AllAfricaGovt loses potential revenue after mine's closure. DTZ-OZGEO alluvial operation.Allafrica.com, June 2, 1/4p.Africa, ZimbabweNews item - DTZ-OZGEO
DM1507-0456
2015
AllAfricaZim sells $ 1.4 million carats of rough diamonds.Allafrica.com, June 11, 1/4p.Africa, ZimbabweNews item - rough
DM1508-0450
2015
AllAfricaRiozim committed to Murowa. Rio Zim held 22 % and now controls the entity after its major shareholder Gem Holdings bought 78 % from Rio Tinto.Allafrica.com, July 16, 1p.Africa, ZimbabweNews item - RioZim
DM1508-0451
2015
AllAfricaDebswana Diamond Company shown commitment to the submission of training and labour.Allafrica.com, July 27, 1/2p.Africa, BotswanaNews item - CSR
DM1508-2482
2015
AllAfricaAngola, Russia discuss co-operation in diamond industry. Catoca, Tchiuzo, LuaxeAllafrica.com, July 2, 1/4p.Africa, AngolaNews item - Alrosa
DM1510-2000
2015
AllAfricaDiamond production increases in country. CatocaAllafrica.com, Aug. 27, 1/4p.Africa, AngolaNews item - production
DM1510-2001
2015
AllAfricaMwadui mine life extended 20 years.Allafrica.com, Sept. 19, 1/4p.Africa, TanzaniaNews item - Petra
DM1512-2210
2015
AllAfricaMarange diamond licences have now expired: minister.. Giving government an advantage for consolidation of the sector.Allafrica.com, Oct. 30, 1p.Africa, ZimbabweNews item - Marange
DM1512-2211
2015
AllAfricaGun thefts leave diamond big shots paranoid. Allafrica.com, Nov. 27, 1/4p.Africa, NamibiaNews item - legal
DM1512-2212
2015
AllAfricaNamibia has 1,5 billion carats at sea. Allafrica.com, Nov. 27, 1/4p.Africa, NamibiaNews item - marine mining
DM1512-2213
2015
AllAfricaDebswana partnership solid in Botswana.Allafrica.com, Nov. 23, 1/4p.Africa, BotswanaNews item - Debswana
DC1503-1383
2015
AlrosaAlrosa reports Q2 production results. H1 2014 results and sales.Alrosa, Jan. 31, 3p.RussiaNews item - press release
DC1505-1384
2015
AlrosaAlrosa Investors-Day presentation. Detailed locations, projects, financialsAlrosa, Apr. 8, 45pptRussiaNews item - Alrosa
DC1505-1385
2015
AlrosaAlrosa's executive Committtee considered the 2014 exploration performance to declare all the targets successfully achieved.info@alrosa.ru, Apr. 17, 2p.RussiaNews item - press release
DC1501-1386
2014
Alto Ventures Ltd.Alto initiates airborne magnetometer survey on its Pikoo area, diamond claims, Saskatchewan.Alto Ventures Lt., Dec. 17, 1p.Canada, SaskatchewanNews item - press release
DC1502-1387
2015
Alto Ventures Ltd.Alto Ventures review of 2014 activities. PikooAlto Ventures Ltd., Jan. 14, 1p.Canada, SaskatchewanNews item - press release
DC1502-1388
2015
Alto Ventures Ltd.Alto Ventures confirms kimberlite indicator minerals on the GEFA property adjacent to Pikoo, Northern Saskatchewan.Alto Ventures Ltd., Jan. 22, 2p.Canada, SaskatchewanNews item - press release
DC1504-1389
2015
Alto Ventures Ltd.Priority targets identified from high resolution airborne magnetic Survey adjacent to Pikoo diamond discovery, northern Saskatchewan.Alto Ventures Ltd., Feb. 26, 2p.Canada, SaskatchewanNews item - press release
DC1505-1390
2015
Alto Ventures Ltd.Alto Ventures recovers kimberlite indicator minerals on the West Fisher claims northwest of the Pikoo diamond discovery, northern Saskatchewan.Alto Ventures Ltd., Apr. 1, 1p.Canada, SaskatchewanNews item - press release
DC1505-1391
2015
Alto Ventures Ltd.Priority targets from high resolution airborne magnetic survey over West Fisher claims northwest of Pikoo diamond discovery, northern Saskatchewan. Alto Ventures Ltd., Apr. 22, 1p.Canada, SaskatchewanNews item - press release
DC1510-2329
2015
Alto Ventures Ltd.Alto Ventures arranges financing plans till sampling on its Pikoo area claims, northern Saskatchewan.Alto Ventures Limited, Sept. 24, 1p.Canada, SaskatchewanNews item - press release
DS1503-0132
2015
Amit, H., Olson, P.Lower mantle superplume growth excites geomagnetic reversals.Earth and Planetary Science Letters, Vol. 414, March 15, pp. 68-76.MantleHotspots

Abstract: Seismic images of the lower mantle reveal two large-scale, low shear wave velocity provinces beneath Africa and the Pacific that are variously interpreted as superplumes, plume clusters or piles of dense mantle material associated with the layer. Here we show that time variations in the height of these structures produce variations in heat flux across the core–mantle boundary that can control the rate at which geomagnetic polarity reversals occur. Superplume growth increases the mean core–mantle boundary heat flux and its lateral heterogeneity, thereby stimulating polarity reversals, whereas superplume collapse decreases the mean core–mantle boundary heat flux and its lateral heterogeneity, inhibiting polarity reversals. Our results suggest that the long, stable polarity geomagnetic superchrons such as occurred in the Cretaceous, Permian, and earlier in the geologic record were initiated and terminated by the collapse and growth of lower mantle superplumes, respectively.
DM1511-2111
2015
Amnesty InternationalChains of abuse: the case of diamonds from the Central African Republic and the global diamond supply chain.Amnestyinternational.org, Sept. 3p.Africa, Central African RepublicNews item - KP, CSR

Abstract: Amnesty International has examined three specific points in the global diamond supply chain, starting with diamonds in the Central African Republic (CAR), moving to two of CAR’s neighbours into which some of its diamonds are smuggled, and ending at diamond exchanges in the major global trading centres of Antwerp and Dubai. CAR has been embroiled in armed conflict since late 2012. The report uses CAR as a case study to examine the diamond supply chain but looks beyond the conflict to human rights abuses in the artisanal mining sector in CAR and to other illegal and unethical practices in the diamond supply chain that cause or contribute to human rights abuses – such as smuggling and tax abuse.
DS1501-0002
2014
Anderson, D.L., King, S.D.Driving the Earth machine?Science, Vol. 346, 6214, pp. 1184-1185.MantleAthenosphere, magmatism

Abstract: The asthenosphere—derived from the Greek asthenes, meaning weak—is the uppermost part of Earth's mantle, right below the tectonic plates that make up the solid lithosphere. First proposed by Barrell 100 years ago (1), the asthenosphere has traditionally been viewed as a passive region that decouples the moving tectonic plates from the mantle and provides magmas to the global spreading ridge system. Recent studies suggest that the asthenosphere may play a more active role as the source of the heat and magma responsible for intraplate volcanoes. Furthermore, it may have a major impact on plate tectonics and the pattern of mantle flow.
DS1510-1756
2014
Andreeva, I.A.Salt ( carbonatite) melts of the Bol'shaya Tagna Massif, the eastern Sayan region: evidence from melt inclusions.Deep-seated magmatism, its sources and plumes, Proceedings of XIII International Workshop held 2014., Vol. 2014, pp. 148-159.RussiaMineral chemistry
DS1502-0038
2015
Angel, R.J., Alvaro, M., Nestola, F., Mazzucchelli, M.L.Diamond thermoelastic properties and implications for determining the pressure of formation of diamond inclusion systems.Russian Geology and Geophysics, Vol. 56, 1-2, pp. 211-220.TechnologyDiamond inclusions

Abstract: The formation conditions of diamond can be determined from the residual pressure of inclusions trapped within the diamond, as measured at ambient conditions, and the equations of state (EoS) of the mineral inclusion and the host diamond. The EoS parameters of the diamond and the inclusion phase are therefore critical for determining the precision and accuracy of the calculation of formation conditions of diamonds. The questions we address are (i) How precise are these calculations? and, in particular, (ii) Do we know the EoS parameters of diamond to a precision and accuracy which do not contribute significantly to uncertainties in the geological conclusions drawn from these calculations? We present a review of the most recent compressional data, simulations, and direct elastic measurements of diamond and show them to be consistent with a room-temperature bulk modulus of K0T = 444(2) GPa and a pressure derivative K = 4.0. In combination with a thermal-pressure model with parameters aV300,0 = 2.672(3) x 10- 6 K- 1 and a single Einstein temperature 0E = 1500 K, the volume variation of diamond from room conditions to pressures and temperatures exceeding those in the Earth’s transition zone is described to within the levels of uncertainty inherent in both experimental and computational determinations. For the example of olivine inclusions in diamond, these uncertainties in the diamond EoS parameters lead to uncertainties in the entrapment pressures of no more than 0.001 GPa at low temperatures and 0.008 GPa at higher temperatures.
DS1503-0133
2015
Araujo e Azevedo, P., Peres Rocha, M., Pereira Soares, J.E., Fuck, R.A.Thin lithosphere beween the Amazonian and Sao Francisco cratons, in central Brazil, revealed by seismic P wave tomography.Geophysical Journal International, Vol. 201, 1, pp. 61-69.South America, BrazilGeophysics - seismic

Abstract: Results of P-wave traveltime seismic tomography in central Brazil unravel the upper-mantle velocity structure and its relationship with the tectonic framework. Data were recorded between 2008 and 2012 at 16 stations distributed over the study area, and were added to the database used by Rocha et al. to improve the resolution of anomalies, and to image the surrounding regions. The main objective was to observe the upper-mantle boundary zone between the Amazonian and São Francisco cratons, represented by mobile belts, inside the Tocantins Province, and to study the lithosphere related to the collision between these two cratons during the Neoproterozoic. A set of low-velocity anomalies was observed crossing the study area in the NE–SW direction, in agreement with the main trend of the Transbrasiliano lineament. The region where the anomalies are located was interpreted as the zone separating the Amazonian and São Franciscan palaeoplates. There is a good correlation between the low-velocity anomalies and the high seismicity of this region, suggesting that it is a region of weakness, probably related to lithospheric thinning. High velocities were observed under the Amazonian and São Francisco cratons. A model is proposed for the lithospheric subsurface in central Brazil, emphasizing the boundary zone between the main palaeoplates in the study area. After merging both databases, the low-velocity anomalies in the central part of the study area suggest tectonic partitioning of the lithosphere. Synthetic tests show that the tomography results are robust.
DC1502-1392
2014
Archangel Diamond CorpLukoil wins dismissal of USA lawsuit over alleged fraud. ( Archangel Diamond Company JV with Arkhangelgeology AGE)OAO Lukoil , Dec. 23, 1p.RussiaNews item - press release
DC1502-1393
2015
Arctic Star Exploration CorporationArctic Star stakes Torrie kimberlite cluster at Lac de Gras.Arctic Star Exploration, Jan. 16, 1p.Canada, Northwest TerritoriesNews item - press release
DC1503-1395
2015
Arctic Star Exploration CorporationArctic Star announces "Stein diamond project", Nunavut Canada.Arctic Star Exploration Corporation, Feb. 5, 1p.Canada, NunavutNews item - press release
DC1507-1394
2015
Arctic Star Exploration CorporationArctic Star updates the Redemption diamond project, Lac de Gras.Arctic Star Exploration, June 2, 1p.Canada, Northwest TerritoriesNews item - press release
DC1509-1396
2015
Arctic Star Exploration CorporationArctic Star reports on T-Rex property.Arctic Star Exploration Corporation, Aug. 5, 4p.Canada, Northwest TerritoriesNews item - press release
DS1510-1757
2014
Arzamastev, A.A., Arztmasteva, L.V., Zhirova, A.M., Glaznev, V.N.Model of formation of the Khibiny-Lovozero orebearing volcanic-plutonic complex.Deep-seated magmatism, its sources and plumes, Proceedings of XIII International Workshop held 2014., Vol. 2014, pp. 124-147.Baltic Shield, FennoscandiaCarbonatite, alkaline rocks

Abstract: The paper presents the results of a study of the large Paleozoic ore-magmatic system in the northeastern Fennoscandian Shield comprising the Khibiny and Lovozero plutons, the Kurga intrusion, volcanic rocks, and numerous alkaline dike swarms. As follows from the results of deep drilling and 3D geophysical simulation, large bodies of rocks pertaining to the ultramafic alkaline complex occur at the lower level of the ore-magmatic system. Peridotite, pyroxenite, melilitolite, melteigite, and ijolite occupy more than 50 vol % of the volcanic-plutonic complex within the upper 15 km accessible to gravity exploration. The proposed model represents the ore-magmatic system as a conjugate network of mantle magmatic sources localized at different depth levels and periodically supplying the melts belonging to the two autonomous groups: (1) ultramafic alkaline rocks with carbonatites and (2) alkali syenites-peralkaline syenites, which were formed synchronously having a common system of outlet conduits. With allowance for the available isotopic datings and new geochronological evidence, the duration of complex formation beginning from supply of the first batches of melt into calderas and up to postmagmatic events, expressed in formation of late pegmatoids, was no less than 25 Ma.
DS1502-0039
2015
Ashchepkov, I.The universal Cpx Jd-Di barometer for mantle peridotite eclogite and pyroxenites and its use for mantle petrology.Economic Geology Research Institute 2015, Vol. 17,, # 2121, 1p. AbstractTechnologyBarometer

Abstract: Original monomineral thermobarometers for mantle peridotites for clinopyroxene, garnet, chromite and ilmenites for the mantle peridotites were statistically calibrated on the PT estimates for mantle peridotites [Ashchepkov et al., 2010] were tested using the mineral phases obtained in high pressure experiments with the natural peridotites (380 runs) [Brey et al.,1990; 2008 etc] and eclogites (240 runs)[Dasgupta et al., 2006 etc]. In the original program of that written on FORTRAN are assembled the most reliable methods of mineral thermometers (45) and barometers (36) and oxybarometers (5), including original monomineral and methods [Ashchepkov, 2003 Ashchepkov et al., 2008; 2009; 2010; 2011] for the mantle peridotites bases on the compositions of on clinopyroxene, garnet, chromite and ilmenite. Program reads the text files, which converted from Excel. Original data include standard silicate compositions for 12 components in standard order. The text file includes 15 columns of 8 symbols. The first is file name which is the same for all the minerals in the association. The second is indicator symbol for phases. E- enstatite, D - diopside, O-olivine, S-spinel, G- garnet, I –ilmenite, A- amphibole, F – phlogopite, P-plagioclase, L- liquid, R- bulk rock. Then follow oxides: SiO2, TiO2, Al2O3, Cr2O3, FeO, MnO, MgO, CaO, Na2O, K2O, NiO, V2O3 written with 2–3 decimals. The last column may contain description of the mineral or association up to 64 symbols. Monomineral methods use calculated values for Fe#Ol or Fe#Cpx. The input from console includes file name (8 symbols) (A8), then amount of PT pairs of numbers thermometers and barometers (2I2) and one for FO2 method. Program allows input of the iteration numbers (to 25 by default). It allow to choose whether to use the calculated Fe3+ for the minerals and also. It is possible also to put fixed values of T and P (default 1000oC and 40 kbar ).
DS1502-0040
2015
Ashchepkov, I., Ntaflos, T., Spetsius, Z.Trace element study of the xenoliths study of the mantle xenoliths from Sytykanskaya pipe, Yakutia.Economic Geology Research Institute 2015, Vol. 17,, # 2624, 1p. AbstractRussiaDeposit - Sytykanskaya
DS1510-1758
2015
Ashchepkov, I.V., Logvinova, A.M., Reimers, L.F., Ntaflos, T., Spetisus, Z.V., Vladykin, N.V., Downes, H., Yudin, D.S., Travin, A.V., Makovchuk, I.V., Palesskiy, V.S., KhmelNikova, O.S.The Sytykanskaya kimberlite pipe: evidence from deep seated xenoliths and xenocrysts for the evolution of the mantle beneath Alakit, Yakutia, Russia.Geoscience Frontiers, Vol. 6, 5, pp. 687-714.Russia, YakutiaDeposit - Sytykanskaya

Abstract: Mantle xenoliths (>150) and concentrates from late autolithic breccia and porphyritic kimberlite from the Sytykanskaya pipe of the Alakit field (Yakutia) were analyzed by EPMA and LAM ICP methods. In P-T-X-f(O2) diagrams minerals from xenoliths show widest variations, the trends P-Fe#-CaO, f(O2) for minerals from porphyric kimberlites are more stepped than for xenocrysts from breccia. Ilmenite PTX points mark moving for protokimberlites from the lithosphere base (7.5 GPa) to pyroxenite lens (5-3.5 GPa) accompanied by Cr increase by AFC and creation of two trends P-Fe#Ol ~10-12% and 13-15%. The Opx-Gar-based mantle geotherm in Alakit field is close to 35 mW/m2 at 65 GPa and 600 °C near Moho was determined. The oxidation state for the megacrystalline ilmenites is lower for the metasomatic associations due to reduction of protokimberlites on peridotites than for uncontaminated varieties at the lithosphere base. Highly inclined linear REE patterns with deep HFSE troughs for the parental melts of clinopyroxene and garnet xenocrysts from breccia were influenced by differentiated protokimberlite. Melts for metasomatic xenoliths reveal less inclined slopes without deep troughs in spider diagrams. Garnets reveal S-shaped REE patterns. The clinopyroxenes from graphite bearing Cr-websterites show inclined and inflected in Gd spectrums with LREE variations due to AFC differentiation. Melts for garnets display less inclined patterns and Ba-Sr troughs but enrichment in Nb-Ta-U. The 40Ar/39Ar ages for micas from the Alakit mantle xenoliths for disseminated phlogopites reveal Proterozoic (1154 Ma) age of metasomatism in early Rodinia mantle. Veined glimmerites with richterite - like amphiboles mark ~1015 Ma plume event in Rodinia mantle. The ~600-550 Ma stage manifests final Rodinia break-up. The last 385 Ma metasomatism is protokimberlite-related.
DS1510-1759
2014
Ashchepkov, I.V., Vladykin, N.V., Ntaflos, T., Logvinova, A.M., Yudin, D.S., Karpenko, M.A., Paleeskiy, V.S., Alymova, N.V., Khmelnikova, O.S.Deep seated xenoliths and xencrysts from Sytykanskaya pipe: evidence for the evolution of the mantle beneath Alakit, Yakutia.Deep-seated magmatism, its sources and plumes, Proceedings of XIII International Workshop held 2014., Vol. 2014, pp. 203-232.Russia, YakutiaDeposit - Sytykanskaya

Abstract: The concentrate from two phases of the kimberlite (breccia and porphyritic kimberlite) and about 130 xenoliths from the Sytykanskaya pipe of the Alakit field (Yakutia) were studied by EPMA and LAM ICP methods. Reconstructions of the PTXfO2 mantle sections were made separately for the two phases. The porphyritic kimberlites and breccia show differences in the minerals although the layering and pressure interval remains the same. For the porphyritic kimberlite the trends P- Fe# - CaO in garnet, fO2 are sub-vertical while the xenocrysts from the breccia show stepped and curved trends possibly due to interaction with fluids. Minerals within xenoliths show the widest variation in all pressure intervals. PT points for the ilmenites which trace the magmatic system show splitting of the magmatic source into two levels at the pyroxenite lens (4GPa) accompanied by peridotite contamination and an increase in Cr in ilmenites. Two groups of metasomatites with Fe#Ol ~ 10-12% and 13-15% were created by the melts derived from protokimberlites and trace the mantle columns from the lithosphere base (Ilm - Gar - Cr diopside) to Moho becoming essentially pyroxenitic (Cr-diopside with Phl). The first Opx-Gar-based mantle geotherm from the Alakit field has been constructed from15 associations and is close to 35 mw/m2 in the lower part of mantle section but deviates to high temperatures in the upper part of the mantle section. The oxidation state for the protokimberlite melts determined from ilmenites is higher than for the other pipes in the Yakutian kimberlite province which probably accounts for the decrease in the diamond grade of this pipe. The geochemistry of the minerals (garnets and clinopyroxenes) from breccias, metasomatic peridotite xenoliths and pyroxenites systematically differ. Xenocrysts from the breccia were produced by the most differentiated melts and enriched protokimberlite or carbonatite; they show highly inclined nearly linear REE patterns and deep troughs of HFSE. Minerals of the metasomatic xenoliths are less inclined with lower La/Cen ratios and without troughs in spider diagrams. The garnets often show S-shaped patterns. Garnets from the Cr websterites show round REE patterns and deep troughs in Ba-Sr but enrichment in Nb-Ta-U. The clinopyroxenes reveal the inclined and inflected on Gd spectrums with variations in LREE due to AFC differentiation. The 40Ar-39Ar ages for micas from the Alakit field reveal three intervals for the metasomatism. The first (1154 Ma) relates to dispersed phlogopites found throughout the mantle column, and probably corresponds to the continental arc stage in the early stage of Rodinia. Veined highly alkaline and Ti-rich veins with richterite ~1015 Ma corresponds to the plume event within the Rodinia mantle. The ~600-550 Ma stage marks the final Rodinia break-up. The last one near 385 Ma is protokimberlite related.
DC1506-1397
2015
Astro Resources nlHighlights East Kimberley diamonds.Astro Resources nl, Apr. 29, 1p.AustraliaNews item - press release
DC1509-1398
2015
Astro Resources NLEast Kimberley diamonds project ( near Argyle AK1 pipe). Quarterly updateAstro Resources NL, July 30, 12p.AustraliaNews item - press release
DC1512-2414
2015
Astro Resources nlDrilling and geophysical data identified seven priority potential lamproite pipe targets. East KimberleyAstro Resources nl, Oct. 27, 1p AustraliaNews item - press release
DC1502-1399
2015
Athabasca Nuclear CorporationAthabasca Nuclear options Pikoo North diamond project.Athabasca Nuclear Corporation, Jan. 2, 1p.Canada, SaskatchewanNews item - press release
DC1510-2330
2015
Athabasca Nuclear CorporationAthabasca Nuclear Corporation announces commencement of Pikoo airborne survey.Athabasca Nuclear Corporation, Sept. 16, 1p.Canada, SaskatchewanNews item - press release
DC1512-2415
2015
Athabasca Nuclear CorporationProngua Lake project update. Airborne survey.Athabasca Nuclear Corporation, Oct. 29, 1p.Canada, SaskatchewanNews item - press release
DC1512-2416
2015
Athabasca Nuclear CorporationAnnounces Pikoo airborne results at Prongua Lake.Athabasca Nuclear Corporation, Nov. 17, 1p.Canada, SaskatchewanNews item - press release
DS1511-1820
2015
Aulbach , S., Viljoen, K.S.Eclogite xenoliths from the Lace kimberlite, Kaapvaal craton: from convecting mantle source to palaeo-ocean floor and back.Earth and Planetary Science Letters, Vol. 431, pp. 274-286.Africa, South AfricaDeposit - Lace

Abstract: Major- and trace-element compositions of eclogite and pyroxenite xenoliths of =2.5 Ga age (in situ Pb-Pb data on clinopyroxene) from the Lace kimberlite on the Kaapvaal craton were investigated in order to constrain: (1) the nature and evolution of their protoliths; (2) the extent to which they preserve information on the state of the asthenospheric mantle source that gave rise to their low-pressure protoliths; and (3) the effect of their deep recycling on the radiogenic isotope evolution of the convecting mantle. Their elemental relationships are consistent with low-pressure fractionation of olivine ± plagioclase and clinopyroxene during oceanic crust formation, whereby the residual melt was enriched in rare-earth elements (REE), high field-strength elements and Y, producing inverse correlations of SREE with the size of Eu- and Sr-anomalies. LREE-depletion may indicate loss of on average 20% of a partial melt upon subduction and metamorphism (eclogitisation) of oceanic crust, which did not, however, contribute to juvenile growth of continental crust. The eclogites have median Sm/Nd (0.40) and Lu/Hf (0.27) similar to Depleted Mantle, and lower U/Pb (0.02) and Th/Pb (0.02). If deeply subducted, these rocks cannot explain unradiogenic Nd and Hf, and radiogenic Pb isotope compositions in the sources of some modern ocean island basalts. Low incompatible trace-element contents similar to picrites, and Yb concentrations at a given TiO2 content similar to modern MORB, indicate derivation of the protoliths by average melt fractions of ~0.20-0.25~0.20-0.25 that left a spinel peridotite residue at pressures =2.5 to 3.0 GPa. This shallow intersection of the peridotite solidus suggests moderate Archaean ambient mantle potential temperatures of =1420 to 1470?°C. Samples filtered for clinopyroxene fractionation and metasomatism have V/Sc (4.7±1.24.7±1.2; n=11n=11) indicating lower fO2fO2 (-1.9 relative to the fayalite-magnetite-quartz buffer=?FMQbuffer=?FMQ) than modern MORB. This is in part due to the higher average melt extraction pressure (~1.5 GPa) during formation of their crustal protoliths. Extrapolation to 1 GPa, similar to the average pressure of present-day MORB generation, yields ?FMQ of -1.7±1.1-1.7±1.1, corresponding to Fe3+# of 0.07±0.040.07±0.04. If these results are correct, they suggest an Archaean ambient mantle more reducing than at present, with implications for the speciation of volatiles, which affects the mantle solidus and the composition of volcanic gases. This has implications for the Archaean atmospheric redox evolution and the recycling of carbon and other volatiles.
DS1501-0003
2015
Ault, A.K., Flowers, R.M., Bowlring, S.A.Synchroneity of cratonic burial phases and gaps in kimberlite record: episodic magmatism or preservational bias?Earth and Planetary Science Letters, Vol. 410, pp. 97-104.Global, CanadaThermochronology - Slave craton

Abstract: A variety of models are used to explain an apparent episodicity in kimberlite emplacement. Implicit in these models is the assumption that the preserved kimberlite record is largely complete. However, some cratons now mostly devoid of Phanerozoic cover underwent substantial Phanerozoic burial and erosion episodes that should be considered when evaluating models for global kimberlite distributions. Here we show a broad temporal coincidence between regional burial phases inferred from thermochronology and gaps in the kimberlite record in the Slave craton, Superior craton, and cratonic western Australia. A similar pattern exists in the Kaapvaal craton, although its magmatic, deposition, and erosion history differs in key ways from the other localities. One explanation for these observations is that there is a common cause of cratonic subsidence and suppression of kimberlite magmatism. Another possibility is that some apparent gaps in kimberlite magmatism are preservational artifacts. Even if kimberlites occurred during cratonic burial phases, the largest uppermost portions of the pipes would have been subsequently eroded along with the sedimentary rocks into which they were emplaced. In this model, kimberlite magmatism was more continuous than the preserved record suggests, implying that evidence for episodicity in kimberlite genesis should be carefully evaluated in light of potential preservational bias effects. Either way, the correlation between burial and kimberlite gaps suggests that cratonic surface histories are important for understanding global kimberlite patterns.
DS1511-1821
2012
AusIMM JORCAustralasian code for reporting of exploration results, mineral resources and ore reserves. There is a mention of micros in this 2012 version. Tania has updated the next SAMREC version with alluivials and micros which may be available in 2016 and will bJORC Ore Reserves Committee, 2012, 44p. Available pdfGlobalMicrodiamonds - responses
DM1504-0457
2015
Australian MiningArgyle pink diamond coin retailing for a cool $ 8k.Australian Mining, Mar. 4, 1/4p.AustraliaNews item - Argyle
DS1501-0004
2014
Bah, M.D.Mining for peace: diamonds, bauxite, iron ore and political stability in Guinea.Review of African Political Economy, Routledge Pub., Vol. 41, no. 142, pp. 500-515.Africa, GuineaHistory

Abstract: The article explores the relationship between mineral resources and conflict management in Guinea. Literature on theories of recent civil wars and/or armed conflicts in West Africa identifies the combination of abundant natural resources and extreme poverty as a significant trigger of violent civil conflicts. In Guinea, however, despite this combination, the state has managed to avoid large-scale civil violence. This gives rise to the question of why this combination has failed to be associated with the onset of large-scale violence in the country. The article identifies mitigating factors that have contributed to political stability in Guinea. It concludes that measures taken by Guinea and its international partners mitigated the security threats posed by these resources, while keeping most Guineans in abject poverty. This is in contrast to findings in recent quantitative studies whereby natural resource abundance alongside extreme poverty is strongly associated with armed conflicts in West African nations.
DS1507-0303
2015
Bailey, B.L., Blowes, D.W., Smith, L., Sego, D.C.The Diavik waste rock project: geochemical and microbiological characterization of drainage from low sulfide waste rock: active zone field experiments.Applied Geochemistry, Vol. 36, pp. 187-199.Canada, Northwest TerritoriesDeposit - Diavik
DS1512-1896
2015
Bailey, B.L., Blowes, D.W., Smith, L., Sego, D.C.The Diavik waste rock project: geochemical and microbiological characterization of low sulfide content large-scale waste rock test piles.Applied Geochemistry, Vol. 62, pp. 18-34.Canada, Northwest TerritoriesDeposit - Diavik

Abstract: Two experimental waste-rock piles (test piles), each 15 m in height × 60 m × 50 m, were constructed at the Diavik diamond mine in Northern Canada to study the behavior of low-sulfide content waste rock, with a similarly low acid-neutralization potential, in a continuous permafrost region. One test pile with an average of 0.035 wt.% S (<50 mm fraction; referred to as Type I) and a second test pile with an average of 0.053 wt.% S (<50 mm fraction; referred to as Type III) were constructed in 2006. The average carbon content in the <50 mm fraction of waste rock in the Type I test pile was 0.031 wt.% as C and in the Type III test pile was 0.030 wt.% as C. The NP:AP ratio, based on the arithmetic mean of particle-size weighted NP and AP values, for the Type I test pile was 12.2, suggesting this test pile was non-acid generating and for the Type III test pile was 2.2, suggesting an uncertain acid-generating potential. The Type I test pile maintained near-neutral pH for the 4-year duration of the study. Sulfate and dissolved metal concentrations were low, with the exception of Ni, Zn, Cd, and Co in the fourth year following construction. The pore water in the Type III test pile contained higher concentrations of SO42- and dissolved metals, with a decrease in pH to <4.7 and an annual depletion of alkalinity. Maximum concentrations of dissolved metals (20 mg L-1 Ni, 2.3 mg L-1 Cu, 3.7 mg L-1 Zn, 35 µg L-1 Cd, and 3.8 mg L-1 Co) corresponded to decreases in flow rate, which were observed at the end of each field season when the contribution of the total outflow from the central portion of the test pile was greatest. Bacteria were present each year in spite of annual freeze/thaw cycles. The microbial community within the Type I test pile included a population of neutrophilic S-oxidizing bacteria. Each year, changes in the water quality of the Type III test-pile effluent were accompanied by changes in the microbial populations. Populations of acidophilic S-oxidizing bacteria and Fe-oxidizing bacteria became more abundant as the pH decreased and internal test pile temperatures increased. Irrespective of the cold-climate conditions and low S content of the waste rock, the geochemical and microbiological results of this study are consistent with other acid mine drainage studies; indicating that a series of mineral dissolution-precipitation reactions controls pH and metal mobility, and transport is controlled by matrix-dominated flow and internal temperatures.
DS1501-0005
2014
Bain & CompanyThe global diamond report 2014, Diamonds: timeless gems in a changing world. Challenges, financing, supply and demandBain & Company, 84p. Pdf availableGlobalDiamond markets

Abstract: In this year’s edition: Diamonds: Timeless Gems in A Changing World, we focus on key challenges facing the industry, initiatives under way to address them, and possible outcomes that would support the industry’s continued growth. We believe that the challenges explored in this report also present opportunities for all players in the diamond industry and for the investment community. The key challenges include the following: Sustaining demand for diamonds in jewelry and as investments. What models of cooperation are players adopting to spur demand for diamonds, in jewelry and as an investment vehicle? Securing long-term access to diamonds. As long-term supply tapers off, what options can retailers consider? Defining the role of synthetic diamonds. What opportunities and challenges will the continued evolution of synthetic-diamond technologies present to the industry? Ensuring that diamond financing will continue to sustain industry growth. How should the diamond-financing business model evolve to sustain healthy growth for all industry players? As in previous years, the report also identifies key trends along the value chain for rough and polished diamonds as well as diamond jewelry. We compare 2013 results with the results of previous years and highlight the impact of continuing economic uncertainty on the diamond market. We also provide an update on the outlook for the diamond industry through 2024. The 2024 demand outlook is based on our extensive market analysis and research. The updated supply forecast is based on the latest developments among key diamond miners and the largest diamond mines worldwide.
DS1505-0254
2015
Ballmer, M.D., Conrad, C.P., Smith, E.I., Johnsen, R.Intraplate volcanism at the edges of the Colorado Plateau sustained by a combination of triggered edge-driven convection and shear-driven upwelling.Geochemistry, Geophysics, Geosystems: G3, Vol. 16, 2, pp. 366-379.United States, Colorado PlateauConvection

Abstract: Although volcanism in the southwestern United States has been studied extensively, its origin remains controversial. Various mechanisms such as mantle plumes, upwelling in response to slab sinking, and small-scale convective processes have been proposed, but have not been evaluated within the context of rapidly shearing asthenosphere that is thought to underlie this region. Using geodynamic models that include this shear, we here explore spatiotemporal patterns of mantle melting and volcanism near the Colorado Plateau. We show that the presence of viscosity heterogeneity within an environment of asthenospheric shearing can give rise to decompression melting along the margins of the Colorado Plateau. Our models indicate that eastward shear flow can advect pockets of anomalously low viscosity toward the edges of thickened lithosphere beneath the plateau, where they can induce decompression melting in two ways. First, the arrival of the pockets critically changes the effective viscosity near the plateau to trigger small-scale edge-driven convection. Second, they can excite shear-driven upwelling (SDU), in which horizontal shear flow becomes redirected upward as it is focused within the low-viscosity pocket. We find that a combination of “triggered” edge-driven convection and SDU can explain volcanism along the margins of the Colorado Plateau, its encroachment toward the plateau's southwestern edge, and the association of volcanism with slow seismic anomalies in the asthenosphere. Geographic patterns of intraplate volcanism in regions of vigorous asthenospheric shearing may thus directly mirror viscosity heterogeneity of the sublithospheric mantle.
DS1509-0384
2015
Baptiste, V., Demouchy, S., Keshav, S., Parat, F., Bolfan-Casanova, N., Condamine, P., Cordier, P.Decrease of hydrogen incorporation in forsterite from CO2-H2O rich kimberlitic liquid.American Mineralogist, Vol. 100, pp. 1912-1920.TechnologyHydrogen, water

Abstract: To test if hydrogen incorporation by ionic diffusion can occur between a volatile-rich kimberlitic liquid and forsterite, results of high-pressure and high-temperature experiments using a piston-cylinder apparatus at 1200–1300 °C and 1 GPa for durations of 1 min, 5 h, and 23 h, are reported here. Kim-berlitic liquid in the system CaO-MgO-Al 2 O 3-SiO 2-CO 2-H 2 O and synthetic forsterite single crystals were chosen as a first simplification of the complex natural kimberlite composition. Unpolarized Fourier transform infrared spectroscopy was used to quantify the concentrations of OH in the crystallographically oriented forsterite. Scanning electron microscopy, electron backscattered diffraction, electron microprobe analyses, and transmission electron microscopy were performed to identify the run products. After 5 and 23 h, a forsterite overgrowth crystallized with the same orientation as the initial forsterite single crystal. The kimberlitic liquid has crystallized as micrometer-scale euhedral forsterite neocrystals with random crystallographic orientations, as well as a nanoscale aluminous phase and a calcic phase. Despite theoretical water-saturation of the system and long duration, none of the initial forsterite single crystals display signs of hydration such as hydrogen diffusion profile from the border toward the center of the crystal. Most likely, the presence of CO 2 in the system has lowered the H 2 O fugacity to such an extent that there is no significant hydration of the starting forsterite single crystal or its overgrowth. Also, the presence of CO 2 enhances rapid forsterite crystal growth. Forsterite growth rate is around 2 × 10 8 mm 3 /h at 1250 °C. These experimental results suggest a deep mantle origin of the high OH content found in natural mantle-derived xenoliths transported in kimberlites, as reported from the Kaapvaal craton. In agreement with previous studies, it also points out to the fact that significant hydration must take place in a CO 2-poor environment.
DS1504-0183
2015
Barry, P.H., Hilton, D.R., Day, J.M.D., Pernet-Fisher, J.F., Howarth, G.H., Magna, T., Agashev, A.M., Pokhilenko, N.P., Opkhilenko, L.N., Taylor, L.A.Helium isotope evidence for modification of the cratonic lithosphere during the Permo-Triassic Siberian flood basalt event.Lithos, Vol. 216-217, pp. 73-80.Russia, SiberiaDeposit - Udachnaya, Obnazhennaya

Abstract: Major flood basalt emplacement events can dramatically alter the composition of the sub-continental lithospheric mantle (SCLM). The Siberian craton experienced one of the largest flood basalt events preserved in the geologic record — eruption of the Permo-Triassic Siberian flood basalts (SFB) at ~250 Myr in response to upwelling of a deep-rooted mantle plume beneath the Siberian SCLM. Here, we present helium isotope (3 He/ 4 He) and concentra-tion data for petrologically-distinct suites of peridotitic xenoliths recovered from two temporally-separated kim-berlites: the 360 Ma Udachnaya and 160 Ma Obnazhennaya pipes, which erupted through the Siberian SCLM and bracket the eruption of the SFB. Measured 3 He/ 4 He ratios span a range from 0.1 to 9.8 R A (where R A = air 3 He/ 4 He) and fall into two distinct groups: 1) predominantly radiogenic pre-plume Udachnaya samples (mean clinopyroxene 3 He/ 4 He = 0.41 ± 0.30 R A (1s); n = 7 excluding 1 outlier), and 2) 'mantle-like' post plume Obnazhennaya samples (mean clinopyroxene 3 He/ 4 He = 4.20 ± 0.90 R A (1s); n = 5 excluding 1 outlier). Olivine separates from both kimberlite pipes tend to have higher 3 He/ 4 He than clinopyroxenes (or garnet). Helium con-tents in Udachnaya samples ([He] = 0.13–1.35 µcm 3 STP/g; n = 6) overlap with those of Obnazhennaya ([He] = 0.05–1.58 µcm 3 STP/g; n = 10), but extend to significantly higher values in some instances ([He] = 49– 349 µcm 3 STP/g; n = 4). Uranium and thorium contents are also reported for the crushed material from which He was extracted in order to evaluate the potential for He migration from the mineral matrix to fluid inclusions. The wide range in He content, together with consistently radiogenic He-isotope values in Udachnaya peridotites suggests that crustal-derived fluids have incongruently metasomatized segments of the Siberian SCLM, whereas high 3 He/ 4 He values in Obnazhennaya peridotites show that this section of the SCLM has been overprinted by Permo-Triassic (plume-derived) basaltic fluids. Indeed, the stark contrast between pre-and post-plume 3 He/ 4 He ra-tios in peridotite xenoliths highlights the potentially powerful utility of He-isotopes for differentiating between various types of metasomatism (i.e., crustal versus basaltic fluids).
DS1511-1822
2015
Bartels, A., Nielsen, T.F.D., Lee, S.R.G.J., Upton, B.G.J.Petrological and geochemical characteristics of Mesoproterozoic dyke swarms in the Gardar Province, south Greenland: evidence for a major sub-continental lithospheric mantle component in the generation of the magmas.Mineralogical Magazine, Vol. 79, 4, pp. 909-939.Europe, GreenlandDike swarms

Abstract: The Mesoproterozoic Gardar Province in South Greenland developed in a continental rift-related environment. Several alkaline intrusions and associated dyke swarms were emplaced in Archaean and Ketilidian basement rocks during two main magmatic periods at 1300-1250 Ma and 1180-1140 Ma. The present investigation focuses on mafic dykes from the early magmatic period (‘Older Gardar’) and the identification of their possible mantle sources. The rocks are typically fine- to coarse-grained dolerites, transitional between tholeiitic and alkaline compositions with a general predominance of Na over K. They crystallized from relatively evolved, mantle-derived melts and commonly show minor degrees of crustal contamination. Selective enrichment of the large ion lithophile elements Cs, Ba and K and the light rare-earth elements when compared to high field-strength elements indicate significant involvement of a sub-continental lithospheric mantle (SCLM) component in the generation of the magmas. This component was affected by fluid-dominated supra-subduction zone metasomatism, possibly related to the Ketilidian orogeny ~500 Ma years prior to the onset of Gardar magmatism. Melt generation in the SCLM is further documented by the inferential presence of amphibole in the source region, negative calculated eNd(i) values (-0.47 to -4.40) and slightly elevated 87Sr/86Sr(i) (0.702987 to 0.706472) ratios when compared to bulk silicate earth as well as relatively flat heavy rare-earth element (HREE) patterns ((Gd/Yb)N = 1.4-1.9) indicating melt generation above the garnet stability field. The dyke rocks investigated show strong geochemical and geochronological similarities to pene-contemporaneous mafic dyke swarms in North America and Central Scandinavia and a petrogenetic link is hypothesized. Considering recent plate reconstructions, it is further suggested that magmatism was formed behind a long-lived orogenic belt in response to back-arc basin formation in the time interval between 1290-1235 Ma.
DS1511-1823
2004
Barton, E.Small is beautiful… the recovery of microdiamonds helps to predict the presence of commercial sized diamonds.Inside Mining, Vol. 109, July, pp. 32-35. Available pdfAfricaMicrodiamonds - responses

Abstract: The recovery and analysis of microdiamonds helps to predict the presence of commercial-sized diamonds in kimberlites. It is a cost-effective method for prioritising targets for bulk sampling.
DS1503-0136
2015
Bastow, I.D., Eaton, D.W., Kendall, J-M., Helffrich, G., Snyder, D.B., Thompson, D.A., Wookey, J., Darbyshire, F.A., Pawlak, A.E.The Hudson Bay lithospheric experiment ( HuBLE): insights into Precambrian plate tectonics and the development of mantle keels.Geological Society of London Special Publication: Continent formation through time., No. 389, pp. 41-67.Canada, Ontario, QuebecGeotectonics

Abstract: Hudson Bay Lithospheric Experiment (HuBLE) was designed to understand the processes that formed Laurentia and the Hudson Bay basin within it. Receiver function analysis shows that Archaean terranes display structurally simple, uniform thickness, felsic crust. Beneath the Palaeoproterozoic Trans-Hudson Orogen (THO), thicker, more complex crust is interpreted as evidence for a secular evolution in crustal formation from non-plate-tectonic in the Palaeoarchaean to fully developed plate tectonics by the Palaeoproterozoic. Corroborating this hypothesis, anisotropy studies reveal 1.8 Ga plate-scale THO-age fabrics. Seismic tomography shows that the Proterozoic mantle has lower wavespeeds than surrounding Archaean blocks; the Laurentian keel thus formed partly in post-Archaean times. A mantle transition zone study indicates ‘normal’ temperatures beneath the Laurentian keel, so any cold mantle down-welling associated with the regional free-air gravity anomaly is probably confined to the upper mantle. Focal mechanisms from earthquakes indicate that present-day crustal stresses are influenced by glacial rebound and pre-existing faults. Ambient-noise tomography reveals a low-velocity anomaly, coincident with a previously inferred zone of crustal stretching, eliminating eclogitization of lower crustal rocks as a basin formation mechanism. Hudson Bay is an ephemeral feature, caused principally by incomplete glacial rebound. Plate stretching is the primary mechanism responsible for the formation of the basin itself.
DS1502-0041
2014
Batanova, V.G., Lyaskovskaya, Z.E., Savelieva, G.N., Sobolev, A.V.Peridotites from the Kamchatsky Mys: evidence of oceanic mantle melting near a hotspot.Russian Geology and Geophysics, Vol. 55, pp. 1395-1403.RussiaHarzburgite, plumes

Abstract: A suite of mantle peridotites sampled in the Kamchatsky Mys includes spinel lherzolite, clinopyroxene-bearing harzburgite, and harzburgite. Mineral chemistry of olivine, chromian spinel, and clinopyroxene show strongly correlated element patterns typical of peridotite formed by 8% to more than 22% partial melting. Clinopyroxene in the Kamchatka peridotites is compositionally different from that of both abyssal and suprasubduction varieties: Clinopyroxene in lherzolite is depleted in LREE relative to abyssal peridotite and that in harzburgite has very low LREE and Sr unlike the subduction-related counterpart. These composition features indicate that the rocks ultra-depleted in basaltic components originated in the vicinity of a hotspot, possibly, proto-Hawaiian plume, which provided high temperature and melting degree of the MORB source mantle at mid-ocean ridge.
DM1501-0458
2014
Bates, R.Believe it: the lab-grown diamond sector is out promoting the natural diamonds.jckonline.com, Dec. 12, 1p.TechnologyNews item - Pure Grown
DM1502-0459
2015
Bates, R.Being a sightholder is a fool's errand. JSCK Online blog, Jan. 23, 1p.GlobalNews item - De Beers
DC1509-1400
2015
Bauer Foundations Canada Inc.Bauer Group acquires major project to build cut-off wall for diamond mine in Canada. DiavikBauer Foundations Canada Inc., Aug. 1p.Canada, Northwest TerritoriesNews item - press release
DC1503-1401
2015
Beaufort SecuritiesParagon Diamonds … emerging diamond producer with polished upside, fully funded. LemphaneBeaufort Securities Research Report, Feb. 12, 6p.Africa, LesothoNews item - Paragon
DS1512-1897
2015
Belcourt, G.A 2015 geophysical update for Kennady North project, NT.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 16.Canada, Northwest TerritoriesDeposit - Kennady North

Abstract: This presentation will provide an update of geophysical surveys performed in 2015. These surveys were undertaken to aid in the delineation of known kimberlites and discovery of potential kimberlite targets on Kennady Diamonds Inc.'s Kennady North Property. In 2015, Kennady Diamonds Inc. focused most of their geophysical budget on expansion of the known kimberlites. Previous OhmMapper surveys were expanded in the Doyle & MZ Areas in order to provide locations for exploration drilling. Ground based Gravity surveys were completed using an increased sample density in key areas. This increased density in the gravity data proved to be very helpful in the detailed drilling of the Kelvin and Faraday kimberlite bodies. Late in the summer season, a small scale marine seismic system was utilized on the Kelvin and Faraday lakes. This data will hopefully be used to discover potential areas of new or thicker kimberlite under the lake. As the Kelvin and Faraday kimberlites are not the typical pipe-like bodies, many different geophysical tools from our toolbox must be utilized.
DS1506-0256
2015
Bell, K., Zaitsev, A.N., Spratt, J., Frojdo, S., Rukhlov, A.S.Elemental, lead and sulfur isotopic compositions of galena from Kola carbonatites, Russia - implications for melt and mantle evolution.Mineralogical Magazine, Vol. 79, 2, pp. 219-241.RussiaCarbonatite, Kola

Abstract: Galena from four REE-rich (Khibina, Sallanlatvi, Seblyavr, Vuoriyarvi) and REE-poor (Kovdor) carbonatites, as well as hydrothermal veins (Khibina) all from the Devonian Kola Alkaline Province of northwestern Russia was analysed for trace elements and Pb and S isotope compositions. Microprobe analyses show that the only detectable elements in galena are Bi and Ag and these vary from not detectable to 2.23 and not detectable to 0.43 wt.% respectively. Three distinct galena groups can be recognized using Bi and Ag contents, which differ from groupings based on Pb isotope data. The Pb isotope ratios show significant spread with 206Pb/204Pb ratios (16.79 to 18.99), 207Pb/204Pb (15.22 to 15.58) and 208Pb/204Pb ratios (36.75 to 38.62). A near-linear array in a 207Pb/204Pb vs. 206Pb/204Pb ratio diagram is consistent with mixing between distinct mantle sources, one of which formed during a major differentiation event in the late Archaean or earlier. The S isotopic composition (d34S) of galena from carbonatites is significantly lighter (–-6.7 to -–10.3% Canyon Diablo Troilite (CDT) from REE-rich Khibina, Seblyavr and Vuoriyarvi carbonatites, and - 3.2% CDT from REE-poor Kovdor carbonatites) than the mantle value of 0%. Although there is no correlation between S and any of the Pb isotope ratios, Bi and Ag abundances correlate negatively with d34S values. The variations in the isotopic composition of Pb are attributed to partial melting of an isotopically heterogeneous mantle source, while those of d34S (together with Bi and Ag abundances) are considered to be process driven. Although variation in Pb isotope values between complexes might reflect different degrees of interaction between carbonatitic melts and continental crust or metasomatized lithosphere, the published noble gas and C, O, Sr, Nd and Hf isotopic data suggest that the variable Pb isotope ratios are best attributed to isotopic differences preserved within a sub-lithospheric mantle source. Different Pb isotopic compositions of galena from the same complex are consistent with a model of magma replenishment by carbonatitic melts/fluids each marked by quite different Pb isotopic compositions.
DS1505-0249
2015
Belogub, E.V., Krivovichev, S.V., Pekov, I.V., Kuznetsov, A.M., Yapaskurt, V.O., Kitlyarov, V.A., Chukanov, N.V., Belakoviskiy, D.I.Nickelpicromerite, K2Ni(SO4)2*6H2O, a new picromerite group mineral from Slyudorudnik, South Urals, Russia.Mineralogy and Petrology, Vol. 109, 2, pp. 143-152.Russia, UralsMineralogy

Abstract: A new picromerite-group mineral, nickelpicromerite, K2Ni(SO4)2 - 6H2O (IMA 2012-053), was found at the Vein #169 of the Ufaley quartz deposit, near the town of Slyudorudnik, Kyshtym District, Chelyabinsk area, South Urals, Russia. It is a supergene mineral that occurs, with gypsum and goethite, in the fractures of slightly weathered actinolite-talc schist containing partially vermiculitized biotite and partially altered sulfides: pyrrhotite, pentlandite, millerite, pyrite and marcasite. Nickelpicromerite forms equant to short prismatic or tabular crystals up to 0.07 mm in size and anhedral grains up to 0.5 mm across, their clusters or crusts up to 1 mm. Nickelpicromerite is light greenish blue. Lustre is vitreous. Mohs hardness is 2-2½. Cleavage is distinct, parallel to {10-2}. Dmeas is 2.20(2), Dcalc is 2.22 g cm-3. Nickelpicromerite is optically biaxial (+), a = 1.486(2), ß = 1.489(2), ? = 1.494(2), 2Vmeas =75(10)°, 2Vcalc =76°. The chemical composition (wt.%, electron-microprobe data) is: K2O 20.93, MgO 0.38, FeO 0.07, NiO 16.76, SO3 37.20, H2O (calc.) 24.66, total 100.00. The empirical formula, calculated based on 14 O, is: K1.93Mg0.04Ni0.98S2.02O8.05(H2O)5.95. Nickelpicromerite is monoclinic, P21/c, a = 6.1310(7), b = 12.1863(14), c = 9.0076(10) Å, ß = 105.045(2)°, V = 649.9(1) Å3, Z = 2. Eight strongest reflections of the powder XRD pattern are [d,Å-I(hkl)]: 5.386--34(110); 4.312-46(002); 4.240-33(120); 4.085--100(012, 10-2); 3.685-85(031), 3.041-45(040, 112), 2.808-31(013, 20-2, 122), 2.368-34(13-3, 21-3, 033). Nickelpicromerite (single-crystal X-ray data, R = 0.028) is isostructural to other picromerite-group minerals and synthetic Tutton’s salts. Its crystal structure consists of [Ni(H2O)6]2+ octahedra linked to (SO4)2- tetrahedra via hydrogen bonds. K+ cations are coordinated by eight anions. Nickelpicromerite is the product of alteration of primary sulfide minerals and the reaction of the acid Ni-sulfate solutions with biotite.
DS1511-1824
2015
Bergantz, G.W., Schleicher, J.M., Burgisser, A.Open system dynamics and mixing in magma mushes.Nature Geoscience, Vol. 8, 10, pp. 793-796.MantleMagmatism

Abstract: Magma dominantly exists in a slowly cooling crystal-rich or mushy state1, 2, 3. Yet, observations of complexly zoned crystals4, some formed in just one to ten years5, 6, 7, 8, 9, as well as time-transgressive crystal fabrics10 imply that magmas mix and transition rapidly from a locked crystal mush to a mobile and eruptable fluid5, 6. Here we use a discrete-element numerical model that resolves crystal-scale granular interactions and fluid flow, to simulate the open-system dynamics of a magma mush. We find that when new magma is injected into a reservoir from below, the existing magma responds as a viscoplastic material: fault-like surfaces form around the edges of the new injection creating a central mixing bowl of magma that can be unlocked and become fluidized, allowing for complex mixing. We identify three distinct dynamic regimes that depend on the rate of magma injection. If the magma injection rate is slow, the intruded magma penetrates and spreads by porous media flow through the crystal mush. With increasing velocity, the intruded magma creates a stable cavity of fluidized magma that is isolated from the rest of the reservoir. At higher velocities still, the entire mixing bowl becomes fluidized. Circulation within the mixing bowl entrains crystals from the walls, bringing together crystals from different parts of the reservoir that may have experienced different physiochemical environments and leaving little melt unmixed. We conclude that both granular and fluid dynamics, when considered simultaneously, can explain observations of complex crystal fabrics and zoning observed in many magmatic systems.
DS1504-0184
2015
Berryman, E.J., Wunder, B., Wirth, R., Rhede, D., Schettler, G., Franz, G., Heinrich, W.An experimental study on K and Na incorporation in dravitic tourmaline and insight into the origin of diamondiferous tourmaline from the Kokchetav Massif, Kazakhstan.Contributions to Mineralogy and Petrology, Vol. 169, 19p.Russia, KazakhstanDiamondiferous tourmaline

Abstract: Tourmaline was synthesized in the system MgO-Al2O3-B2O3-SiO2-KCl-NaCl-H2O from an oxide mixture and excess fluid at 500-700 °C and 0.2-4.0 GPa to investigate the effect of pressure, temperature, and fluid composition on the relative incorporation of Na and K in dravitic tourmaline. Incorporation of K at the X-site increases with pressure, temperature, and KCl concentration; a maximum of 0.71 K pfu (leaving 0.29 X-vacant sites pfu) was incorporated into K-dravite synthesized at 4.0 GPa, 700 °C from a 4.78 m KCl, Na-free fluid. In contrast, Na incorporation depends predominately on fluid composition, rather than pressure or temperature; dravite with the highest Na content of 1.00 Na pfu was synthesized at 0.4 GPa and 700 °C from a 3.87 m NaCl and 1.08 m KCl fluid. All synthesized crystals are zoned, and the dominant solid solution in the Na- and K-bearing system is between magnesio-foitite [?(Mg2Al)Al6Si6O18(BO3)3(OH)3OH] and dravite [NaMg3Al6Si6O18(BO3)3(OH)3(OH)], with the dravitic component increasing with the concentration of Na in the fluid. In the K-bearing, Na-free system, the dominant solid solution is between magnesio-foitite and K-dravite [KMg3Al6Si6O18(BO3)3(OH)3(OH)], with the K-dravitic component increasing with pressure, temperature, and the concentration of K in the fluid. The unit-cell volume of tourmaline increases with K incorporation from 1555.1(3) to 1588.1(2) Å3, reflecting the incorporation of the relatively large K+ ion. Comparison of our results to the compositional data for maruyamaite (K-dominant tourmaline) from the ultrahigh-pressure rocks of the Kokchetav Massif in Kazakhstan suggests that the latter was formed in a K-rich, Na-poor environment at ultrahigh-pressure conditions near the diamond-stability field.
DS1510-1760
2015
Beyer, C.Geobarometry, phase relations and elasticity of eclogite under conditions of Earth's upper mantle. IN ENGLISHThesis, Doctoral Beyreuther Graduiertenschule fur Mathematik und Naturwissenschaften IN: ENGLISH, 222p. Available pdfMantleGeobarometry

Abstract: Eclogite rocks, composed mainly of garnet and clinopyroxene, form principally as a metamorphic product of oceanic crust as it undergoes subduction. The equilibrium between garnet and clinopyroxene is sensitive to temperature and pressure, therefore eclogitic outcrops and xenoliths can reveal important information on the chemical and mineralogical processes occurring during such episodes. This is particularly the case for lithospheric eclogitic xenoliths from Archean cratons, which can potential reveal information on ancient (> 1 Ga) subduction events. To obtain information on the depth of origin of eclogitic xenoliths the first project of this thesis was designed to establish a thermodynamically grounded geobarometer, which is based on the incorporation of tetrahedrally coordinated aluminum in clinopyroxene coexisting with garnet: 2/3 Ca3Al2Si3O12 + 1/3 Mg3Al2Si3O12 = CaAl2SiO6 + CaMgSi2O6 Grossular Pyrope CaTs Diopside The reaction was calibrated against high-pressure and high-temperature experiments carried out in the multi-anvil and piston-cylinder apparatus between pressures of 3 and 7 GPa and temperatures from 1200 to 1550 °C. Starting materials were hydrous and anhydrous synthetic mixtures of basaltic bulk compositions that yielded homogeneous bimineralic garnet-clinopyroxene phase assemblages. The experimental data set was expanded by employing results from previous experimental studies conducted in eclogitic systems, which widened the range of applicable conditions and compositions. The calibration reproduces experimental pressures of bimineralic eclogite assemblages, in addition to SiO2-saturated and kyanite-bearing eclogites, to within 0.4 GPa at the 95 % confidence interval. The barometer was then used to examine equilibration pressures recorded by natural mantle eclogites from various xenolith locations covering a wide pressure, temperature, and compositional range. The results seem to indicate that many eclogite xenoliths fall towards the hotter side of the range of geothermal temperatures displayed by peridotitic xenoliths from the same localities. The second project calibrates the composition of majoritic garnets, which contain excess silicon substituted onto the octahedrally coordinated garnet site, coexisting with clinopyroxene as a function of pressure, temperature and bulk composition. Majorite substitution for a given bulk composition increases with pressure, and its proportion can in principal be used as a geobarometer. Single majoritic garnet crystals are found as inclusions in diamonds, which are generally used to support a sublithospheric origin in the deeper upper mantle or transition zone. The chemical compositions of such inclusions indicate that they have formed from a number of different lithologies, including mafic, ultramafic and pyroxenitic. These inclusions give important insight into the environment where diamonds crystallize and the evolution of deep subducted crustal material. The empirical barometer studied here is based on the three major majoritic substitutions: 2Al3+ = Mg2+ + Si4+ (Mj), Mg2+ + Al3+ = Na1+ + Si4+ (NaSi), Mg2+ + Al3+ = Na1+ + Ti4+ (NaTi), and the secondary effect of chromium on the stability of Mj. The barometer was calibrated against experiments conducted in the multi-anvil apparatus between pressures of 6 and 16 GPa and temperatures of 1000 to 1400 °C. In order to expand the applicability to a wide range of compositions experiments were performed in three different mafic compositions and in one pyroxenitic composition. Moreover, existing experimental data in mafic and ultramafic systems, including mid-ocean ridge basalts, kimberlite, komatiite and peridotite bulk compositions were included in the calibration covering pressures from 6 to 20 GPa and temperatures from 900 to 2200 °C. Applying the geobarometer to natural majoritic diamond inclusions reveals clearly that eclogitic and pyroxenitic inclusions form dominantly at conditions near the top of the transition zone (300-400 km). Peridotitic inclusions, however, have formed generally at shallower depths ~200 km within the Earth’s upper mantle. This may reflect the differences expected for the oxygen fugacity between peridotitic and eclogitic/pyroxenitic rocks. If diamonds form through the reduction of carbonate or CO2 bearing melts then most peridotitic rocks would be already within the diamond stability field by depths of 200 km. At greater pressures carbon would remain immobilized as diamond and there is no mechanism by which new diamonds can form. Eclogitic rocks formed by the subduction of oceanic crust, however, should form an intrinsically more oxidized environment that remains within the carbonate stability field to much higher pressures. The diamond stability field would be eventually reached, however, due to either the effect of pressure on controlling Fe3+/Fe2+ equilibria or due to partial melting, which would preferentially remove ferric iron and lower the Fe3+/?Fe of the residue, on which the oxygen fugacity is mainly dependent. In fact deep partial melting as slabs heat up may be the mechanism by which both the local oxygen fugacity is lowered, carbon is mobilized and pyroxenite rocks are formed, with the latter occurring through reaction with the surrounding peridotite. The third project was focused on the elasticity of garnet solid solutions formed from eclogitic compositions. Garnet is an important mineral because it is a major phase in the upper mantle and dominates mafic rocks at these conditions. The elastic behavior of garnet solid solutions plays a role in the interpretation of seismic data and is important for estimating the density contrast between subducting slabs and the surrounding mantle. High-precision single-crystal X-ray diffraction measurements at high pressure have been conducted on three different ternary garnet solid solutions with varying chemical composition in order to examine possible non-ideal contributions to the volume and compressibility of garnet solid solutions. Furthermore one experiment has been conducted at high pressures and high temperatures to examine the effect of temperature on the elasticity of complex garnet solid solutions. Experimental results reveal that the concentration of the almandine (Fe3Al2Si3O12) component has a significant effect on the elasticity, whereby 10 - 20 mole% of almandine is sufficient to overprint the previously reported minima of the bulk modulus along the pyrope grossular join. It has also been shown that minor compositional variations of Ca and Mg within the Mg Fe Ca garnet ternary are not resolvable within the analytical errors. Therefore, the two eclogitic samples have similar bulk moduli within the analytical uncertainties. In contrast to previous studies, no evidence was found that garnets have a K’ significantly different from 4. The high-temperature experiment revealed that the relatively small fraction of almandine in a solid solution increased the softening of garnet with temperature. Finally, the experimental volumes and calculated densities have been compared to the self-consistent thermodynamic model of Stixrude and Lithgow-Bertelloni (2005, 2011). The comparison clearly reveals that volume and elastic properties cannot be linearly interpolated as a function of composition. Moreover, it has been shown that the excess properties vary not only as a function of composition and pressure, but also as a function of temperature. The final project is focused on the partitioning of fluorine (F) between garnet, clinopyroxene, and silicate melt within eclogitic compositions. Fluorine is the most abundant halogen on Earth and plays an important role in the formation of ultrapotassic lithologies, i.e. lamproites that contain several wt.% F, in contrast to the average lithospheric mantle that contains only tens of µg/g F. The cycling and partitioning behavior of fluorine in the Earth’s mantle are not well understood. High-pressure experiments have been conducted in the multi-anvil apparatus to obtain mineral-melt partition coefficients between garnet, clinopyroxene, and coexisting silicate melt of fluorine in a mafic system under conditions of the Earth’s upper mantle. The results show that mafic crust can host significantly more fluorine than the surrounding ultramafic mantle, due to the much higher proportion of clinopyroxene and its high fluorine partition coefficient of D_F^(clinopyroxene/melt)= 0.057 - 0.074. Combining the fluorine partitioning data with water partitioning data yields a plausible process to generate lamproitic magmas with a high F/H2O ratio. The enrichment of fluorine relative to H2O is triggered by multiple episodes of small degree melting which deplete the residual more in H2O than in fluorine, caused by the approximately three times smaller mineral-melt partition coefficients of H2O.
DS1503-0134
2015
Beyer, C., Frost, D.J., Miyajima, N.Experimental calibration of a garnet-clinopyroxene geobarometer for mantle eclogites.Contributions to Mineralogy and Petrology, Vol. 169, 21p.MantleGeobarometry - eclogites

Abstract: Thermodynamic parameters have been calibrated for a geobarometer suitable for use on eclogitic mantle xenoliths. The barometer is based on the incorporation of tetrahedrally coordinated aluminum in clinopyroxene coexisting with garnet and has been calibrated using the results of piston cylinder and multi-anvil experiments performed between pressures of 3 and 7 GPa and temperatures from 1,200 to 1,550 °C. Starting materials were hydrous and anhydrous synthetic mixtures of basaltic bulk compositions that yielded homogeneous bimineralic garnet-clinopyroxene phase assemblages. The experimental data set was expanded by employing results from previous experimental studies conducted in eclogitic systems, which widened the range of applicable conditions and compositions. The calibration reproduces experimental pressures of bimineralic eclogite assemblages, in addition to SiO2-saturated and kyanite-bearing eclogites, to within 0.4 GPa at the 95 % confidence interval. The barometer was then used to examine equilibration pressures recorded by natural mantle eclogites from various xenolith locations covering a wide pressure, temperature, and compositional range.
DM1508-0460
2015
Biesheuver, T.The missing diamond shortage.Bloomberg.news, July 3, 3p.GlobalNews item - markets
DS1512-1898
2015
Blacklock, S.Ekati diamond mine UAVs.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 18.Canada, Northwest TerritoriesDeposit - Ekati

Abstract: Dominion Diamond Ekati Corporation (DDEC) purchased two unmanned aerial vehicles (UAV's) in 2014 to assist in surveying the active open pits and kimberlite stockpiles at the mine. UAV technology has allowed the team to survey various aspects of the mine in a safer and more accurate. manner. Along with making day to day work more efficient, DDEC surveying now has the ability to complete various other requests from departments at the mine. These include; large area photographs of lay downs, new road alignments, projects and environmental areas of interest.
DS1504-0185
2015
Block, S., Ganne, J., Baratoux, A.Z., Parra-Avila, L.A., Jessell, M., Ailleres, L., Siebenaller, L.Petrological and geochronological constraints on lower crust exhumation during Paleoproterozoic (Eburnean) Orogeny, NW Ghana, West African craton.Journal of Metamorphic Geology, Vol. 33, 5, pp. 463-494.Africa, GhanaGeochronology

Abstract: New petrological and geochronological data are presented on high-grade ortho- and paragneisses from northwestern Ghana, forming part of the Paleoproterozoic (2.25-2.00 Ga) West African Craton. The study area is located in the interference zone between N-S and NE--SW-trending craton-scale shear zones, formed during the Eburnean orogeny (2.15-2.00 Ga). High-grade metamorphic domains are separated from low-grade greenstone belts by high-strain zones, including early thrusts, extensional detachments and late-stage strike-slip shear zones. Paragneisses sporadically preserve high-pressure, low-temperature (HP-LT) relicts, formed at the transition between the blueschist facies and the epidote-amphibolite sub-facies (10.0-14.0 kbar, 520-600 °C), and represent a low (~15 °C km-1) apparent geothermal gradient. Migmatites record metamorphic conditions at the amphibolite-granulite facies transition. They reveal a clockwise pressure-temperature-time (P-T-t) path characterized by melting at pressures over 10.0 kbar, followed by decompression and heating to peak temperatures of 750 °C at 5.0-8.0 kbar, which fit a 30 °C km-1 apparent geotherm. A regional amphibolite facies metamorphic overprint is recorded by rocks that followed a clockwise P-T-t path, characterized by peak metamorphic conditions of 7.0-10.0 kbar at 550-680 °C, which match a 20-25 °C km-1 apparent geotherm. These P-T conditions were reached after prograde burial and heating for some rock units, and after decompression and heating for others. The timing of anatexis and of the amphibolite facies metamorphic overprint is constrained by in-situ U-Pb dating of monazite crystallization at 2138 ± 7 and 2130 ± 7 Ma respectively. The new data set challenges the interpretation that metamorphic breaks in the West African Craton are due to diachronous Birimian ‘basins’ overlying a gneissic basement. It suggests that the lower crust was exhumed along reverse, normal and transcurrent shear zones and juxtaposed against shallow crustal slices during the Eburnean orogeny. The craton in NW Ghana is made of distinct fragments with contrasting tectono-metamorphic histories. The range of metamorphic conditions and the sharp lateral metamorphic gradients are inconsistent with ‘hot orogeny’ models proposed for many Precambrian provinces. These findings shed new light on the geodynamic setting of craton assembly and stabilization in the Paleoproterozoic. It is suggested that the metamorphic record of the West African Craton is characteristic of Paleoproterozoic plate tectonics and illustrates a transition between Archean and Phanerozoic orogens.
DS1502-0042
2015
Bloodworth, A.The high stakes race to satisfy our need for the scarcest metals on Earth. Book by K. Veronese Publ. PrometheusNature, Vol. 517, 7533, Jan. 8, pp. 142-143.GlobalBook review - REE
DM1502-0461
2015
BloombergX-ray scanners ordered by Debswana to catch Botswana gem thieves. Jwaneng, Orapa, Letlhakane and Damtshaa.bloomberg.com, Jan. 6, 1p.Africa, BotswanaNews item - Debswana
DM1502-0462
2015
BloombergIsrael gem buyers scared of De Beers profit squeeze. bloomberg.com, Jan. 21, 1p.Europe, IsraelNews item - De Beers
DM1502-0463
2015
BloombergNamibia resumes diamond sales talks with Anglo's De Beers unit. bloomberg.com, Jan. 22, 1p.Africa, NamibiaNews item - Namdeb
DM1509-0464
2015
BloombergWant to make a diamond in just 10 weeks? Use a microwave.bloomberg.com, Aug. 27, 2p.TechnologyNews item - synthetics
DM1512-2214
2015
BloombergDiamonds aren't forever for Botswana as mining boom fades.bloomberg.com, Nov. 5, 1p.Africa, BotswanaNews item - economics
DM1512-2215
2015
BloombergWas billionaire Steinmetz betrayed by CEO over diamond mine? Koidubloomberg.com, Nov. 11, 5p.Africa, Sierra LeoneNews item - Steinmetz
DM1509-1999
2015
Bluedax.comRough market report: July sight - is the system bankrupt.Idex online, July 26, 2p.GlobalNews item - sights
DS1512-1899
2015
Bluemel, B., Dunn, C., Hart, C., Leijd, M.Biogeochemical expressions of buried REE mineralization at Norra Karr, southern Sweden.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 231-240.TechnologyRare earths

Abstract: Biogeochemical exploration is an effective but underutilized method for delineating covered mineralization. Plants are capable of accumulating rare earth elements (REEs) in their tissue, and ferns (pteridophytes) are especially adept because they are one of the most primitive land plants, therefore lack the barrier mechanisms developed by more evolved plants. The Norra Kärr Alkaline Complex, located in southern Sweden approximately 300km southwest of Stockholm, is a peralkaline nepheline syenite enriched in heavy rare earth elements (HREEs). The deposit, roughly 300m wide, 1300m long, and overlain by up to 4 m of Quaternary sediments, has been well-defined by diamond drilling. The inferred REE mineral resource, over 60 million tonnes averaging 0.54% Total Rare Earth Oxide (TREO), is dominantly hosted within the pegmatitic “grennaite” unit, a eudialyte-catapleiite-aegerine nepheline syenite. Vegetation and soil samples were collected from the surficial environment above Norra Kärr to address four key questions: which plant species is the most effective biogeochemical exploration medium; what are the annual and seasonal REE variations in that plant; how do the REEs move through the soil profile; and into which part of the plant are they concentrated. Athyrium filix-femina (lady fern) has the highest concentration of LREEs and HREEs (up to 125.17ppm Ce and 1.03ppm Dy) in its dry leaves; however, there is better contrast between background and anomalous areas in Dryopteris filix-mas (wood fern), which makes it the preferred biogeochemical sampling medium. The REE content in all fern species was shown to decrease from root > frond > stem, and chondrite normalized REE patterns within the plant displayed preferential fractionation of the LREEs in the fronds relative to the roots. Samples collected from an area directly overlying the deposit had up to five times greater HREE content (0.74ppm Dy) in August than the same plants did in June (0.14ppm Dy). The elevated REE content and distinct contrast to background demonstrate that biogeochemical sampling is an effective method for REE exploration in this environment.
DC1506-1403
2015
BlueRock Diamonds Plc.BlueRock Diamonds' Kareevlei plant delayed by crusher commissioning.BlueRock Diamonds Plc., May 1, 1p.Africa, South AfricaNews item - press release
DC1507-1404
2015
BlueRock Diamonds plc.Blue Rock Diamonds sells 116 carat parcel for average of USD440 per carat.Bluerock Diamonds plc., June 25, 1p.Africa, South AfricaNews item - press release
DC1511-2370
2015
BlueRock Diamonds plc.Interim results .. Summary Kareevlei Wes kimberlite.BlueRock Diamonds plc., Sept. 30, 3p.Africa, South AfricaNews item - press release
DC1512-2417
2015
BlueRock Diamonds plc.Finalization of contract with Diacar and operational update.. KareevleiBlueRock Diamonds Plc, Nov. 5, 1p.Africa, South AfricaNews item - press release
DS1509-0385
2015
Boger, S.D., Hirdes, W., Ferreira, C.A.M., Jenett, T., Dallwig, R., Fanning, C.M.The 580-520 Ma Gondwana suture of Madagascar and its continuation into Antarctica and Africa.Gondwana Research, Vol. 28, pp. 1048-1060.Africa, MadagascarTectonics

Abstract: U-Pb age data from southwest Madagascar provide a compelling case that the pre-Gondwana Indian plate was stitched with the arc terranes of the Arabian Nubian Shield along a suture that closed between 580 Ma and 520 Ma. The key observations supportive of this interpretation are: (1) metamorphism dated to 630-600 Ma is manifested only on the west side of the suture in rocks that have affinities with the oceanic and island arc terranes of the Arabian Nubian Shield, or which represent continental rocks welded to these terranes prior to the amalgamation of Gondwana, and (2) orogenesis at 580-520 Ma is manifest in rocks on both sides of the suture, an observation taken to mark the timing of collision and to reflect spatial continuity across the suture. In southwest Madagascar the distribution of metamorphic ages places the suture along the Beraketa high-strain zone, the tectonic boundary between the Androyen and Anosyen domains. Similar age relationships allow for the extrapolation of this tectonic boundary into both East Antarctica and Africa.
DS1502-0043
2015
Bogina, M., Zlobin, V., Sharkov, E., Chistyakov, A.Petrogenesis of siliceous high-Mg series rocks as exemplified by the Early Paleoproterozoic mafic volcanic rocks of the Eastern Baltic Shield: enriched mantle versus crustal contamination.Economic Geology Research Institute 2015, Vol. 17,, #3510, 1p. AbstractRussiaPlume geodynamics

Abstract: The Early Paleoproterozoic stage in the Earth's evolution was marked by the initiation of global rift systems, the tectonic nature of which was determined by plume geodynamics. These processes caused the voluminous emplacement of mantle melts with the formation of dike swarms, mafic-ultramafic layered intrusions, and volcanic rocks. All these rocks are usually considered as derivatives of SHMS (siliceous high-magnesian series). Within the Eastern Baltic Shield, the SHMS volcanic rocks are localized in the domains with different crustal history: in the Vodlozero block of the Karelian craton with the oldest (Middle Archean) crust, in the Central Block of the same craton with the Neoarchean crust, and in the Kola Craton with a heterogeneous crust. At the same time, these rocks are characterized by sufficiently close geochemical characteristics: high REE fractionation ((La/Yb)N = 4.9-11.7, (La/Sm)N=2.3-3.6, (Gd/Yb)N =1.66-2.74)), LILE enrichment, negative Nb anomaly, low to moderate Ti content, and sufficiently narrow variations in Nd isotope composition from -2.0 to -0.4 epsilon units. The tectonomagmatic interpretation of these rocks was ambiguous, because such characteristics may be produced by both crustal contamination of depleted mantle melts, and by generation from a mantle source metasomatized during previous subduction event. Similar REE patterns and overlapping Nd isotope compositions indicate that the studied basaltic rocks were formed from similar sources. If crustal contamination en route to the surface would play a significant role in the formation of the studied basalts, then almost equal amounts of contaminant of similar composition are required to produce the mafic rocks with similar geochemical signatures and close Nd isotopic compositions, which is hardly possible for the rocks spaced far apart in a heterogeneous crust. This conclusion is consistent with analysis of some relations between incompatible elements and their ratios. In particular, the rocks show no correlation between Th/Ta and La/Yb, (Nb/La)pm ratio and Th content, and eNd and (Nb/La)N ratio. At the same time, some correlation observed in the eNd-Mg# and (La/Sm)N-(Nb/La)N diagrams in combination with the presence of inherited zircons in the rocks does not allow us to discard completely the crustal contamination. Examination of Sm/Yb-La/Sm relations and the comparison with model melting curves for garnet and spinel lherzolites showed that the parental melts of the rocks were derived by 10-30% mantle melting at garnet-spinel facies transition. Two stage model can be proposed to explain such remarkable isotope-geochemical homogeneity of the mafic volcanic rocks over a large area: (1) ubiquitous emplacement of large volumes of sanukitoid melts in the lower crust of the shield at 2.7 Ga; (2) underplating of plume-derived DM melts at the crust-mantle boundary, melting of the lower crust of sanukitoid composition, and subsequent mixing of these melts with formation of SHMS melts at 2.4 Ga. A simple mixing model showed that in this case the Nd isotope composition of obtained melts remained practically unchanged at variable amounts of contaminant (up to 30%). This work was supported by the RFBR no. 14-05-00458.
DS1502-0044
2015
Bonetto, S., Facello, A., Ferrero, A-M., Umili, G.A tool for semi-automatic linear feature detection based on DTM.Computers & Geosciences, Vol. 75, pp. 1-12.TechnologyNot specific to diamonds
DM1502-0465
2015
Bonner, H.Hason Stevens: why I believe diamonds are a good 5 year play.Sprottglobal.com, Jan.12, 4p. GraphsGlobalNews item - demand
DS1511-1825
2014
Bosshart, G., Chapman, J.The Argyle diamond mine in transition from open pit to underground extraction.Australian Gemmologist, Vol. 24, 1, pp. 4-8.AustraliaDeposit - Argyle

Abstract: At the Argyle diamond mine in Western Australia, an underground project is using block caving techniques to reach deeper portions of the diamondiferous lamproite. This program could extend the life of the mine to 2018. It entails a high level of automation, as well as measures to combat monsoonal downpours.
DC1504-1405
2015
Botswana Diamonds plc.Field exploration update - Orapa, Botswana ( Alrosa). PL 206,207,210Botswana Diamonds plc., Mar. 5, 2p.Africa, BotswanaNews item - press release
DC1504-1406
2015
Botswana Diamonds plc.New licence in Orapa, Botswana. PL 085/2015 to Atlas Minerals ( the local subsidiary company) Botswana Diamonds plc., Mar. 24, 1p.Africa, BotswanaNews item - press release
DC1505-1407
2015
Botswana Diamonds plc.Interim results for the six months to 31 December 2014. JV AlrosaBotswana Diamonds plc., Mar. 27, 3p.Africa, BotswanaNews item - press release
DC1505-1408
2015
Botswana Diamonds plc.Botswana Diamonds Plc. Fundraising of lbs 282,500.Botswana Diamonds plc., Mar. 31, 1p.Africa, BotswanaNews item - press release
DC1505-1409
2015
Botswana Diamonds plc.Botswana Diamonds expands exploration with three new licences in the central part of Botswana. ( Alrosa)Botswana Diamonds plc., Apr. 15, 1p.Africa, BotswanaNews item - press release
DC1507-1410
2015
Botswana Diamonds plc.Exploration update - June 2015. Fieldwork .. Anomaly PL210/2014 drill programme and more work on PL206 & 207. AlrosaBotswana Diamonds plc., June 18, 1p.Africa, BotswanaNews item - press release
DC1510-2331
2015
Botswana Diamonds plc.Update on exploration in Botswana. Orapa region .. PL 206, PL 210, PL 085 and then onto Gope region.Botswana Diamonds plc, Sept. 3, 2p.Africa, BotswanaNews item - press release
DC1510-2332
2015
Botswana Diamonds plc.Exploration update: Joint Venture with Alrosa, drilling starting on PL210, work on new Gope prospecting licencesBotswana Diamonds plc, Sept. 11, 2p.Africa, BotswanaNews item - Botswana Diamonds, Alrosa
DC1511-2371
2015
Botswana Diamonds plc.Exploration update on Licence PL 210 drilling in Orapa.Botswana Diamonds plc., Oct. 7, 1p.Africa, BotswanaNews item - press release
DC1511-2372
2015
Botswana Diamonds plc.New prospecting licence awarded in the Orapa region of Botswana PL260/2015 to Sunland Minerals ( JV Alrosa)Botswana Diamonds plc., Oct. 9, 1p.Africa, BotswanaNews item - press release
DC1512-2418
2015
Botswana Diamonds plc.Preliminary results for the year ended 30 June 2015.Botswana Diamonds plc., Nov. 19, 13p.Africa, BotswanaNews item - press release
DS1503-0135
2015
Bouhifd, M.A., Boyet, M., Cartier, C., Hammouda, T., Bofan-Casanova, N., Devidal, J.L., Andrault, D.Superchondritic Sm/Nd ratio of the Earth: impact of Earth's core formation.Earth and Planetary Science Letters, Vol. 413, March 1, pp. 158-166.MantleGeochronology

Abstract: This study investigates the impact of Earth's core formation on the metal-silicate partitioning of Sm and Nd, two rare-earth elements assumed to be strictly lithophile although they are widely carried by the sulphide phases in reducing material (e.g. enstatite chondrites). The partition coefficients of Sm and Nd (DSmDSm and DNdDNd) between molten CI and EH chondrites model compositions and various Fe-rich alloys (in the Fe-Ni-C-Si-S system) have been determined in a multi-anvil between 3 and 26 GPa at various temperatures between 2073 and 2440 K, and at an oxygen fugacity ranging from 1 to 5 log units below the iron-wüstite (IW) buffer. The chemical compositions of the run products and trace concentrations in Sm and Nd elements were determined using electron microprobe and laser ablation inductively coupled plasma-mass spectrometry. Our results demonstrate the non-fractionation of Sm and Nd during the segregation of the metallic phases: the initial Sm/Nd ratio of about 1 in the starting materials yields precisely the same ratio in the recovered silicate phases after the equilibration with the metal phases at all conditions investigated in this study. In addition, DSmDSm and DNdDNd values range between 10-310-3 and 10-510-5 representing a low solubility in the metal. An increase of the partition coefficients is observed with decreasing the oxygen fugacity, or with an increase of S content of the metallic phase at constant oxygen fugacity. Thus, based on the actual Sm and Nd concentrations in the bulk Earth, the core should contain less than 0.4 ppb for Sm and less than 1 ppb for Nd. These estimates are three orders of magnitude lower than what would be required to explain the reported 142Nd excess in terrestrial samples relative to the mean chondritic value, using the core as a Sm-Nd complementary reservoir. In other words, the core formation processes cannot be responsible for the increase of the Sm/Nd ratio in the mantle early in Earth history.
DS1511-1826
2015
Boyd, O.S., Smalley, R., Zeng, Y.Crustal deformation in the New Madrid seismic zone and the role of postseismic processes.Journal of Geophysical Research, Vol. 120, 8, pp. 5782-5803.United States, ArkansasGeophysics - seismics

Abstract: Global Navigation Satellite System data across the New Madrid seismic zone (NMSZ) in the central United States over the period from 2000 through 2014 are analyzed and modeled with several deformation mechanisms including the following: (1) creep on subsurface dislocations, (2) postseismic frictional afterslip and viscoelastic relaxation from the 1811–1812 and 1450 earthquakes in the NMSZ, and (3) regional strain. In agreement with previous studies, a dislocation creeping at about 4 mm/yr between 12 and 20 km depth along the downdip extension of the Reelfoot fault reproduces the observations well. We find that a dynamic model of postseismic frictional afterslip from the 1450 and February 1812 Reelfoot fault events can explain this creep. Kinematic and dynamic models involving the Cottonwood Grove fault provide minimal predictive power. This is likely due to the smaller size of the December 1811 event on the Cottonwood Grove fault and a distribution of stations better suited to constrain localized strain across the Reelfoot fault. Regional compressive strain across the NMSZ is found to be less than 3?×?10-9/yr. If much of the present-day surface deformation results from afterslip, it is likely that many of the earthquakes we see today in the NMSZ are aftershocks from the 1811–1812 New Madrid earthquakes. Despite this conclusion, our results are consistent with observations and models of intraplate earthquake clustering. Given this and the recent paleoseismic history of the region, we suggest that seismic hazard is likely to remain significant.
DS1506-0257
2015
Bradley, D.The promise of perovskite ( solar)Chemistry Views, May 5, 2p.TechnologyEnergy
DS1502-0045
2014
Brazil diamond mapMap of diamonds from the Patos Meeting.Mapa Simposio APL Diamantes A3 QT.pdf, pdf available 12306KSouth America, BrazilDiamond locations in A.P.
DC1503-1411
2015
Brazil Minerals Inc.Receives title to 25% of a company with 10 mining concessions for diamond and gold. RST Recursos Minerals, Ltda.Brazil Minerals, Inc., Feb. 22, 1p.South America, BrazilNews item - press release
DC1504-1412
2015
Brazil Minerals Inc.Extinguishes 46% of convertible debt note.Brazil Minerals, Inc., Mar. 9, 1p.South America, BrazilNews item - press release
DC1505-1413
2015
Brazil Minerals Inc.Brazil Minerals, Inc. reports largest rough diamond & expected further cash flows from sand products.Brazil Minerals, Inc., Apr. 6, 1p.South America, BrazilNews item - press release
DC1506-1414
2015
Brazil Minerals Inc.Strong preliminary result for new diamond and gold area. Along the margins of Jequithonha River.Brazil Minerals, Inc., Apr. 27, 1p.South America, BrazilNews item - press release
DC1506-1415
2015
Brazil Minerals Inc.Brazil Minerals, Inc. completes first phase of geological assessment of new diamond & gold area. Jequitinhonha river.Brazil Minerals, Inc., May 26, 2p.South America, Brazil, Minas GeraisNews item - press release
DC1508-1416
2015
Brazil Minerals Inc.Brazil Minerals, Inc. receives environmental permit for mining in new diamond and gold area. Jequitinhonka River ( inland old course).Brazil Minerals, Inc., July 13, 1p.South America, BrazilNews item - press release
DC1509-1417
2015
Brazil Minerals Inc.Finishes second phase of geological assessment of new diamond and gold area & completes payment for its RST ownership position.Brazil Minerals, Inc., Aug. 3, 2p.South America, BrazilNews item - press release
DC1510-2333
2015
Brazil Minerals Inc.Brazil Minerals, Inc. provides general update. Comments on gravel potential.Brazil Minerals, Inc., Sept. 21, 1p.South America, BrazilNews item - press release
DC1512-2419
2015
Brazil Minerals Inc.Provides updates on new access road and agreement with investor group to purchase outstanding convertible debt. Brazil Minerals, Inc., Nov. 3, 1p.South America, BrazilNews item - press release
DS1507-0305
2015
Brett, R.C.The ascent of kimberlite: insights from olivine.Earth and Planetary Science Letters, Vol. 424, pp. 119-131.Canada, Northwest Territories, Africa, TanzaniaDeposit - Diavik, Igwisi Hills

Abstract: Olivine xenocrysts are ubiquitous in kimberlite deposits worldwide and derive from the disaggregation of mantle-derived peridotitic xenoliths. Here, we provide descriptions of textural features in xenocrystic olivine from kimberlite deposits at the Diavik Diamond Mine, Canada and at Igwisi Hills volcano, Tanzania. We establish a relative sequence of textural events recorded by olivine during magma ascent through the cratonic mantle lithosphere, including: xenolith disaggregation, decompression fracturing expressed as mineral- and fluid-inclusion-rich sealed and healed cracks, grain size and shape modification by chemical dissolution and abrasion, late-stage crystallization of overgrowths on olivine xenocrysts, and lastly, mechanical milling and rounding of the olivine cargo prior to emplacement. Ascent through the lithosphere operates as a "kimberlite factory" wherein progressive upward dyke propagation of the initial carbonatitic melt fractures the overlying mantle to entrain and disaggregate mantle xenoliths. Preferential assimilation of orthopyroxene (Opx) xenocrysts by the silica-undersaturated carbonatitic melt leads to deep-seated exsolution of CO2-rich fluid generating buoyancy and supporting rapid ascent. Concomitant dissolution of olivine produces irregular-shaped relict grains preserved as cores to most kimberlitic olivine. Multiple generations of decompression cracks in olivine provide evidence for a progression in ambient fluid compositions (e.g., from carbonatitic to silicic) during ascent. Numerical modelling predicts tensile failure of xenoliths (disaggregation) and olivine (cracks) over ascent distances of 2-7 km and 15-25 km, respectively, at velocities of 0.1 to >4 m?s-1. Efficient assimilation of Opx during ascent results in a silica-enriched, olivine-saturated kimberlitic melt (i.e. SiO2 >20 wt.%) that crystallizes overgrowths on partially digested and abraded olivine xenocrysts. Olivine saturation is constrained to occur at pressures <1 GPa; an absence of decompression cracks within olivine overgrowths suggests depths <25 km. Late stage (<25 km) resurfacing and reshaping of olivine by particle-particle milling is indicative of turbulent flow conditions within a fully fluidized, gas-charged, crystal-rich magma.
DS1509-0386
2015
Brey, G.P., Girnis, A.V., Bulatov, V.K., Hofer, H.E., Gerdes, A., Woodland, A.B.Reduced sediment melting at 7.5-12 Gpa: phase relations, geochemical signals and diamond nucleation.Contributions to Mineralogy and Petrology, Vol. 170, 25p.TechnologyExperimental petrology

Abstract: Melting of carbonated sediment in the presence of graphite or diamond was experimentally investigated at 7.5–12 GPa and 800–1600 °C in a multianvil apparatus. Two starting materials similar to GLOSS of Plank and Langmuir (Chem Geol 145:325–394, 1998) were prepared from oxides, carbonates, hydroxides and graphite. One mixture (Na-gloss) was identical in major element composition to GLOSS, and the other was poorer in Na and richer in K (K-gloss). Both starting mixtures contained ~6 wt% CO2 and 7 wt% H2O and were doped at a ~100 ppm level with a number of trace elements, including REE, LILE and HFSE. The near-solidus mineral assemblage contained a silica polymorph (coesite or stishovite), garnet, kyanite, clinopyroxene, carbonates (aragonite and magnesite-siderite solid solution), zircon, rutile, bearthite and hydrous phases (phengite and lawsonite at <9 GPa and the hydrous aluminosilicates topaz-OH and phase egg at >10 GPa). Hydrous phases disappear at ~900 °C, and carbonates persist up to 1000-1100 °C. At temperatures >1200 °C, the mineral assemblage consists of coesite or stishovite, kyanite and garnet. Clinopyroxene stability depends strongly on the Na content in the starting mixture; it remains in the Na-gloss composition up to 1600 °C at 12 GPa, but was not observed in K-gloss experiments above 1200 °C. The composition of melt or fluid changes gradually with increasing temperature from hydrous carbonate-rich (<10 wt% SiO2) at 800-1000 °C to volatile-rich silicate liquids (up to 40 wt% SiO2) at high temperatures. Trace elements were analyzed in melts and crystalline phases by LA ICP MS. The garnet-melt and clinopyroxene-melt partition coefficients are in general consistent with results from the literature for volatile-free systems and silicocarbonate melts derived by melting carbonated peridotites. Most trace elements are strongly incompatible in kyanite and silica polymorphs (D < 0.01), except for V, Cr and Ni, which are slightly compatible in kyanite (D > 1). Aragonite and Fe-Mg carbonate have very different REE partition coefficients (D Mst-Sd/L ~ 0.01 and D Arg/L ~ 1). Nb, Ta, Zr and Hf are strongly incompatible in both carbonates. The bearthite/melt partition coefficients are very high for LREE (>10) and decrease to ~1 for HREE. All HFSE are strongly incompatible in bearthite. In contrast, Ta, Nb, Zr and Hf are moderately to strongly compatible in ZrSiO4 and TiO2 phases. Based on the obtained partition coefficients, the composition of a mobile phase derived by sediment melting in deep subduction zones was calculated. This phase is strongly enriched in incompatible elements and displays a pronounced negative Ta-Nb anomaly but no Zr-Hf anomaly. Although all experiments were conducted in the diamond stability field, only graphite was observed in low-temperature experiments. Spontaneous diamond nucleation and the complete transformation of graphite to diamond were observed at temperatures above 1200-1300 °C. We speculate that the observed character of graphite-diamond transformation is controlled by relationships between the kinetics of metastable graphite dissolution and diamond nucleation in a hydrous silicocarbonate melt that is oversaturated in C.
DC1502-1418
2014
Britannia Mining Inc.Diamonds in transit to north east initiate precious stones commodities contract.Britannia Mining, Inc., Dec. 22, 1p.TechnologyNews item - press release
DC1505-1419
2015
Britannia Mining Inc.Announces two key hires for its diamond division ( Commodities trading division)Britannia Mining, Inc., Mar. 31, 1p.United StatesNews item - press release
DS1502-0046
2014
Brown, R., Summerfield, M., Gleadow, A., Gallagher, K., Carter, A., Beucher, R., Wildman, M.Intracontinental deformation in southern Africa during the Late Cretaceous.Journal of African Earth Sciences, Vol. 100, pp. 20-41.Africa, NamibiaGeothermometry

Abstract: Intracontinental deformation accommodated along major lithospheric scale shear zone systems and within associated extensional basins has been well documented within West, Central and East Africa during the Late Cretaceous. The nature of this deformation has been established by studies of the tectonic architecture of sedimentary basins preserved in this part of Africa. In southern Africa, where the post break-up history has been dominated by major erosion, little evidence for post-break-up tectonics has been preserved in the onshore geology. Here we present the results of 38 new apatite fission track analyses from the Damara region of northern Namibia and integrate these new data with our previous results that were focused on specific regions or sections only to comprehensively document the thermo-tectonic history of this region since continental break-up in the Early Cretaceous. The apatite fission track ages range from 449 ± 20 Ma to 59 ± 3 Ma, with mean confined track lengths between 14.61 ± 0.1 µm (SD 0.95 µm) to 10.83 ± 0.33 µm (SD 2.84 µm). The youngest ages (c. 80–60 Ma) yield the longest mean track lengths, and combined with their spatial distribution, indicate major cooling during the latest Cretaceous. A simple numerical thermal model is used to demonstrate that this cooling is consistent with the combined effects of heating caused by magmatic underplating, related to the Paraná-Etendeka continental flood volcanism associated with rifting and the opening of the South Atlantic, and enhanced erosion caused by major reactivation of major lithospheric structures within southern Africa during a key period of plate kinematic change that occurred in the South Atlantic and SW Indian ocean basins between 87 and 56 Ma. This phase of intraplate tectonism in northern Namibia, focused in discrete structurally defined zones, is coeval with similar phases elsewhere in Africa and suggests some form of trans-continental linkage between these lithospheric zones.
DS1507-0306
2015
Brushan, S.K.Geology of the Kamthai rare earth deposit. Journal of the Geological Society of India, Vol. 85, 5, pp. 537-546.India, RajasthanCalciocarbonatite

Abstract: A wide spectrum of calciocarbonatites and associated alkaline rocks are exposed around Kamthai, Rajasthan. The mineralogical studies exhibit a bimodal distribution of REE minerals. The southeastern block has carbocernaite and the eastern block has bastnaesite ± ancylite / synchysite as the dominant REE minerals followed by parisite and other accessory minerals. Calcite is the most abundant of the gangue phase, followed by biotite, albite, k-feldspar and iron oxide / hydroxide. Minor and trace gangue phases include pyrite, ilmenite, apatite, siderite, ankerite, amphibole, pyroxene, strontianite, barite, ilmenite / pyrophanite, celestine, clay minerals, sphalerite, pyrochlore, fluorite and Mn-rich phases including hollandite and Mn-Fe oxides. Calciocarbonatite occuring as intrusive veins, sills/dykes and plug, is perhaps a product of crystallization of a primary carbonatite melt generated at upper mantle. The first phase magmatic calciocarbonatite is alvikite type, rich in carbocernaite whereas second hydrothermal phase, sovite type, is enriched in bastnaesite. The absence of supergene activity and minerals (crandalite, florencite, gorceixite) indicate minor role of secondary enrichment. A rift-related mechanism, thermal equivalent to Deccan flood basalt (65±2 Ma), invoking "Reunion plume - continental hot spot" might have triggered Tertiary alkaline magmatism.
DS1507-0307
2015
Bucher, K., Stober, I., Muller-Sigmund, H.Weathering crusts on peridotite.Contributions to Mineralogy and Petrology, Vol. 169, pp. 52-Europe, SpainDeposit - Ronda

Abstract: Chemical weathering of dark-green massive peridotite, including partly serpentinized peridotite, produces a distinct and remarkable brown weathering rind when exposed to the atmosphere long enough. The structure and mineral composition of crusts on rocks from the Ronda peridotite, Spain, have been studied in some detail. The generic overall weathering reaction serpentinized peridotite + rainwater = weathering rind + runoff water describes the crust-forming process. This hydration reaction depends on water supply from the outcrop surface to the reaction front separating green peridotite from the brown crust. The reaction pauses after drying and resumes at the front after wetting. The overall net reaction transforms olivine to serpentine in a volume-conserving replacement reaction. The crust formation can be viewed as secondary serpentinization of peridotite that has been strongly altered by primary hydrothermal serpentinization. The reaction stoichiometry of the crust-related serpentinization is preserved and reflected by the composition of runoff waters in the peridotite massif. The brown color of the rind is caused by amorphous Fe(III) hydroxide, a side product from the oxidation of Fe(II) released by the dissolution of fayalite component in olivine.
DS1512-1900
2015
Burnham, A.D., Thomson, A.R., Bulanova, G.P., Kohn, S.C., Smith, C.B., Walter, M.J.Stable isotope evidence for crustal recycling as recorded by superdeep diamonds.Earth and Planetary Science Letters, Vol. 432, pp. 374-380.South America, BrazilDeposit - Juina-5, Collier-4, Machado River

Abstract: Sub-lithospheric diamonds from the Juina-5 and Collier-4 kimberlites and the Machado River alluvial deposit in Brazil have carbon isotopic compositions that co-vary with the oxygen isotopic compositions of their inclusions, which implies that they formed by a mixing process. The proposed model for this mixing process, based on interaction of slab-derived carbonate melt with reduced (carbide- or metal-bearing) ambient mantle, explains these isotopic observations. It is also consistent with the observed trace element chemistries of diamond inclusions from these localities and with the experimental phase relations of carbonated subducted crust. The 18O-enriched nature of the inclusions demonstrates that they incorporate material from crustal protoliths that previously interacted with seawater, thus confirming the subduction-related origin of superdeep diamonds. These samples also provide direct evidence of an isotopically anomalous reservoir in the deep (=350 km) mantle.
DS1504-0186
2015
Burtseva, M.V., Ripp, G.S., Posokhov, V.F., Zyablitsev, A.Yu., Murzintseva, A.E.The sources of fluids for the formation of nephritic rocks of the southern folded belt of the Siberian craton.Doklady Earth Sciences, Vol. 460, 1, pp. 82-86.Russia, SiberiaAlkaline rocks, nephrites
DM1502-0466
2015
Business StandardRio Tinto strikes diamonds in Bundelkhand's Bunder.business standard.com, Jan. 8, 1p.IndiaNews item - Rio Tinto
DS1502-0047
2015
Buslov, M.M., Dobretsov, N.L., Vovna, G.M., Kiselev, V.I.Structural location, composition, and geodynamic nature of diamond bearing metamorphic rocks of the Kokchetav subduction-collision zone of the Central Asian Fold Belt ( Northern Kazakhstan).Russian Geology and Geophysics, Vol. 56, 1-2, pp. 64-80.Russia, KazakhstanKokchetav massif

Abstract: We present data on different aspects of geology, mineralogy, petrology, geochemistry, and geochronology of diamond-bearing metamorphic rocks of the Kumdy-Kol terrane, which show the similarity of their protolith to the sedimentary rocks of the Kokchetav microcontinent. The structural location of the studied objects in the accretion-collision zone evidences that the subduction of the Kokchetav microcontinent beneath the Vendian-Cambrian Ishim-Selety island arc is the main mechanism of transport of graphite-bearing terrigenous-carbonate rocks to zones of their transformation into diamond-bearing metamorphic rocks. The sedimentary rocks of the Kokchetav microcontinent, which are enriched in graphite and iron sulfides and carbonates, contain all components necessary for diamond crystallization in deep-seated subduction zone. This is in agreement with the experimental data and the compositions of fluid-melt inclusions in the minerals of diamond-bearing rocks.
DS1504-0187
2015
Bussweiler, Y., Foley, S.F., Prelevic, D., Jacob, D.E.The olivine macrocryst problem: new insights from minor and trace element compositions of olivine from Lac de Gras kimberlites, Canada.Lithos, Vol. 220-223, pp. 238-252.Canada, Northwest TerritoriesDeposit - Ekati field

Abstract: This study presents detailed petrographical and geochemical investigations on remarkably fresh olivines in kimberlites from the EKATI Diamond Mine- located in the Tertiary/Cretaceous Lac de Gras kimberlite field within the Slave craton of Canada. Olivine, constituting about 42 vol.% of the analyzed samples, can be divided into two textural groups: (i) macrocrystic olivines, > 100 µm sub-rounded crystals and (ii) groundmass olivines, < 100 µm subhedral crystals. Olivines from both populations define two distinct chemical trends; a “ "mantle trend" with angular cores, showing low Ca (< 0.1 wt.% CaO) and high Ni (0.3-0.4 wt.% NiO) at varying Mg# (0.86-0.93), contrasts with a "melt trend" typified by thin (< 100 µm) rims with increasing Ca (up to 1.0 wt.% CaO) and decreasing Ni (down to 0.1 wt.% NiO) contents at constant Mg# (~ 0.915). These findings are in agreement with recent studies suggesting that virtually all olivine is composed of xenocrystic (i.e. mantle-related) cores with phenocrystic (i.e. melt-related) overgrowths, thereby challenging the traditional view that the origin of kimberlitic olivine can be distinguished based on size and morphology. The two main trends can be further resolved into sub-groups refining the crystallization history of olivine; the mantle trend indicates a multi-source origin that samples the layered lithosphere below the Slave craton, whereas the melt trend represents multi-stage crystallization comprising a differentiation trend starting at mantle conditions and a second trend controlled by the crystallization of additional phases (e.g. chromite) and changing magma conditions (e.g. oxidation). These trends are also seen in the concentrations of trace elements not routinely measured in olivine (e.g. Na, P, Ti, Co, Sc, Zr). Trace element mapping with LA-ICP-MS reveals the distribution of these elements within olivine grains. The trace element distribution between the two trends appears to be consistent with phenocrystic olivine overgrowths mainly originating from dissolved orthopyroxene, showing enrichment in Zr, Ga, Nb, Sc, V, P, Al, Ti, Cr, Ca and Mn in the melt trend. In a sample of magmatic kimberlite from the Leslie pipe, the amount of xenocrystic and phenocrystic olivine is estimated to be around 23 vol.% and 19 vol.%, respectively. Subtraction of this xenocrystic olivine from the Leslie bulk composition, aimed at estimating the parental kimberlite melt, results in a minor decrease of Mg# (by about 0.01) and SiO2 content (by about 3 wt.%), whereas CaO increases (by about 3 wt.%).
DS1512-1901
2015
Butler, R.Destructive sampling ethics… protect natural sites, rock outcrops… code of ethics.Nature Geoscience, Vol. 8, 11, pp. 817-818.GlobalCSR
DS1511-1827
2015
Cai, Y-C., Fan, H-R., Santsh, M., Hu, F-F., Yang, K-F, Hu, Z.Subduction related metasomatism of the lithospheric mantle beneath the southeastern North China Craton: evidence from mafic to intermediate dykes in the northern Sulu orogen.Tectonophysics, Vol. 659, pp. 137-151.ChinaSulu orogen - dykes

Abstract: The widespread mafic to intermediate dykes in the northern Sulu orogen provide important constrains on mantle source characteristics and geodynamic setting. Here we present LA-ICPMS zircon U-Pb ages which indicate that the dykes were emplaced during Early Cretaceous (~ 113-108 Ma). The rocks show SiO2 in the range of 46.2 to 59.5 wt.% and alkalic and shoshonitic affinity with high concentrations of MgO (up to 7.6 wt.%), Cr (up to 422 ppm) and Ni (up to 307 ppm). They are enriched in light rare earth elements LREE (La, Ce, Pr, Nd, Sm and Eu) and large ion lithophile elements (LILE, Rb, Sr, Ba, U and Th) and show strong depletion in high field strength elements (HFSE, Nb, Ta, Ti and P). The dykes possess uniformly high (87Sr/86Sr)i (0.70824-0.70983), low eNd(t) (- 14.0 to - 17.4) and (206Pb/204Pb)i (16.66-17.02) and negative eHf(t) (- 23.5 to - 13.7). Our results suggest that the source magma did not undergo any significant crustal contamination during ascent. The systematic variation trends between MgO and major and trace elements suggest fractionation of olivine and clinopyroxene. The highly enriched mantle source for these rocks might have involved melts derived from the subducted lower crust of Yangtze Craton that metasomatized the ancient lithospheric mantle of the North China Craton.
DS1509-0387
2015
Campeny, M., Kamenetsky, V.S., Melgarejo, J.C., Mangas, J., Manuel, J., Alfonso, P., Kamenetsky, M.B., Bambi, A.C.J.M., Goncalves, A.O.Carbonatitic lavas in Catanda ( Kwanza Sul, Angola): mineralogical and geochemical constraints on the parental melt.Lithos, Vol. 232, pp. 1-11.Africa, AngolaCarbonatite

Abstract: A set of small volcanic edifices with tuff ring and maar morphologies occur in the Catanda area, which is the only locality with extrusive carbonatites reported in Angola. Four outcrops of carbonatite lavas have been identified in this region and considering the mineralogical, textural and compositional features, we classify them as: silicocarbonatites (1), calciocarbonatites (2) and secondary calciocarbonatites produced by the alteration of primary natrocarbonatites (3). Even with their differences, we interpret these lava types as having been a single carbonatite suite related to the same parental magma. We have also estimated the composition of the parental magma from a study of melt inclusions hosted in magnetite microphenocrysts from all of these lavas. Melt inclusions revealed the presence of 13 different alkali-rich phases (e.g., nyerereite, shortite, halite and sylvite) that argues for an alkaline composition of the Catanda parental melts. Mineralogical, textural, compositional and isotopic features of some Catanda lavas are also similar to those described in altered natrocarbonatite localities worldwide such as Tinderet or Kerimasi, leading to our conclusion that the formation of some Catanda calciocarbonatite lavas was related to the occurrence of natrocarbonatite volcanism in this area. On the other hand, silicocarbonatite lavas, which are enriched in periclase, present very different mineralogical, compositional and isotopic features in comparison to the rest of Catanda lavas. We conclude that its formation was probably related to the decarbonation of primary dolomite bearing carbonatites.
DC1506-1420
2015
Canadian International Minerals Inc.Kimberlite indicator minerals recovered from Pikoo East properties.Canadian International Minerals Inc., Apr. 27, 2p.Canada, SaskatchewanNews item - press release
DC1509-1421
2015
Canadian International Minerals Inc.Acquires Arc diamond project. Southwest of Pikoo field. ( Mountain Province and Consolidated Pine Channel Gold previous worked)Canadian International Minerals Inc., Aug. 21, 2p.Canada, SaskatchewanNews item - press release
DC1510-2334
2015
Canadian International Minerals Inc.Fixed wing magnetic survey to be flown on Pikoo East properties.Canadian International Minerals Inc., Sept. 14, 2p.Canada, SaskatchewanNews item - press release
DC1510-2335
2015
Canadian Mining JournalDiamonds, NWT, and how the Polar Bear got in there. Logo and diamond policy framework mentions Gahcho Kue.Canadain Mining Journal, Sept. p. 8.Canada, Northwest TerritoriesNews item - Diamond Policy Framework
DC1504-1422
2015
CanAlaska Uranium Ltd.CanAlaska Uranium reports on multiple projects Maguire Lake.CanAlaska Uranium Ltd., Mar. 2, 1p.Canada, ManitobaNews item - press release
DC1502-1423
2015
Canterra Minerals CorporationCanterra stakes the Rex property, NT.Canterra Minerals Corporation, Jan. 20, 1p.Canada, Northwest TerritoriesNews item - press release
DC1503-1424
2015
Canterra Minerals CorporationCanterra receives preliminary gravity survey data for Marlin project, southern Slave, NT.Canterra Minerals Corporation, Jan. 26, 2p.Canada, Northwest TerritoriesNews item - press release
DC1507-1425
2015
Canterra Minerals CorporationCanterra provides exploration update on southern Slave properties, NWT. Canterra Minerals Corporation, June 17, 2p.Canada, Northwest TerritoriesNews item - press release
DC1508-1426
2015
Canterra Minerals CorporationCanterra announces $ 1 million financing 0.06 cts and flow through unit @ 0.08ctsCanterra Minerals Corporation, July 8, 1p.Canada, Northwest Territories, AlbertaNews item - press release
DC1510-2336
2015
Canterra Minerals CorporationCanterra commences exploration program on South Slave properties, NT.Canterra Minerals Corporation, Sept. 3, 1p.Canada, Northwest TerritoriesNews item - press release
DC1512-2420
2015
Canterra Minerals CorporationCanterra completes exploration program, appoints new director and extends financing. Hilltop property Great Slave areaCanterra Minerals Corporation, Nov. 17, 1p.Canada, Northwest TerritoriesNews item - press release
DS1502-0048
2015
Cathles, L.M.Future Rx: optimism, preparation, acceptance of risk.In: Ore deposits of an evolving Earth, Geological Society of London,, Special Publication no. 393, pp. 303-324.GlobalEconomics
DS1502-0049
2015
Cawood, P., Hawkesworth, C.J.Temporal relations between mineral deposits and global tectonic cycles.In: Ore deposits of an evolving Earth, Geological Society of London,, Special Publication no. 393, pp. 9-21.GlobalTectonics

Abstract: Mineral deposits are heterogeneously distributed in both space and time, with variations reflecting tectonic setting, evolving environmental conditions, as in the atmosphere and hydrosphere, and secular changes in the Earth’s thermal history. The distribution of deposit types whose settings are tied to plate margin processes (e.g. orogenic gold, volcanic-hosted massive sulphide, Mississippi valley type Pb-Zn deposits) correlates well with the supercontinent cycle, whereas deposits related to intra-cratonic settings and mantle-driven igneous events, such as Ni-Cu-PGE deposits, lack a clear association. The episodic distribution of deposits tied to the supercontinent cycle is accentuated by selective preservation and biasing of rock units and events during supercontinent assembly, a process that encases the deposit within the assembled supercontinent and isolates it from subsequent removal and recycling at plate margins.
DS1509-0388
2015
Cawthorn, R.G.The geometry and emplacement of the Pilanesberg Complex, South Africa.Geological Magazine, Vol. 152, 5, pp. 802-812.Africa, South AfricaAlkalic

Abstract: The circular 625 km2 alkaline Pilanesberg Complex, South Africa, contains coeval eruptive and several distinctive intrusive syenitic and foyaitic components, concentrically arranged at the surface. However, owing to poor outcrop the relationships between the different intrusive rocks, and their shape in the third dimension cannot be convincingly determined in the field. The original interpretation was a laccolith, whereas later models suggested a funnel shape, and appealed to ring-dyke and cone-sheet emplacement mechanisms. However, the radial widths of these coarse-grained bodies are over 1 km and so cannot have been emplaced as ring dykes or cone sheets, which are usually quite thin and fine grained. Creating the space for emplacement and removal of pre-existing country rocks for each postulated subsequent intrusive event presents a major challenge to this latter hypothesis. Extensive previously published and new field relationships are re-evaluated here to suggest that the body is a gently inward-dipping sheet and that subsequent injections of magma merely pumped up an existing and evolving magma chamber rather than intruded into solid rocks. A Bouguer gravity anomaly model is presented that supports the concept of a shallow, flat-bottomed body rather than one that continues to significant depth. There are many analogies with the Kangerlussuaq Intrusion, Greenland.
DS1512-1902
2015
Cayer, E.M., Winterburn, P.A., Elliott, B.Development of geochemical exploration technologies for the discovery of concealed kimberlites under glacial overburden, NWT.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 22.Canada, Northwest TerritoriesGeochemistry

Abstract: Attention is being focused on the development of deep penetrating geochemical exploration methods as the discovery rate of world class deposits decreases. Diamondiferous kimberlites located in the Lac de Gras region of the Northwest Territories are one of the many deposit types in Canada covered by glacial overburden, and are therefore challenging to detect. This paper presents initial results from an investigation of the DO-18 kimberlite (Peregrine Diamonds), buried under 5-20m of glacial cover, to identify surface geochemical responses directly related to the buried kimberlite and differentiate between physical and chemical transport mechanisms. A detailed grid of 150 samples over an area of 0.5km2 sampled the oxidized upper B soil horizon in till above and off the DO-18 kimberlite into background. Regolith mapping was conducted and included surficial soil type and rock fragments, topographic variation and physical features, e.g. bogs, swamps, vegetation and glacial direction indicators. This allows an assessment of surface controls on the geochemistry, including the generation of false anomalies from chemical traps such as swamps. Multi-element geochemistry comprising 4-acid, Aqua-Regia and distilled water extraction coupled with ICP-MS was undertaken using commercial techniques to identify and differentiate between those elements migrating by chemical process from those migrating by physical transportation. Hydrocarbons were analysed using the SGH-technique (ActLabs) and the Gore-sorber technique (AGI) to characterize type and abundance of complex hydrocarbons above the kimberlite relative to the host granite gneiss. Preliminary results from the 4-acid digestion data show a clastic dispersion of Nb, Ni, Mg, Co, Cr and Cs from directly above the kimberlite to the edge of the sampling grid 500 metres northwest of the buried kimberlite. Surface material exhibits a strong control on geochemistry with trace elements being controlled by major elements (Al, Fe, Mn) found within each surface material type, and in some cases are heavily influenced by the presence of organic carbon. Evaluation of these relationships allows clarification of the natural background noise and enhancement of the geochemical responses and contrasts.
DM1501-0467
2014
CBC NewsWork starts on winter road network in Ontario. VictorCbcnews.ca, Dec. 9, 1p.Canada, OntarioNews item - ice roads
DM1502-2464
2015
CBC NewsTaken alone, NWT exploration figures fail to impress.Cbcnews.ca, Jan. 22, 1/2p.Canada, Northwest TerritoriesNews item - spending
DM1503-0468
2015
CBC NewsClock ticking on Ekati mine expansion: Dominion Diamond Corporation. Company says current timeline of environmental assessment could delay construction, prompt layoffs.Cbcnews.ca, Jan. 25, 1p.Canada, Northwest TerritoriesNews item - Dominion
DM1503-0469
2015
CBC NewsN.W.T. to study diamond mine ice road into all-season road. Cbcnews.ca, Jan. 29, 1/4p.Canada, Northwest TerritoriesNews item - ice road
DM1504-0470
2015
CBC NewsSnap Lake mine could close if dissolved solid limit not raised: De Beers. Company asking Mackenzie Valley Land and Water Board to nearly triple limit.Cbcnews.ca, Mar. 13, 2p.Canada, Northwest TerritoriesNews item - De Beers
DM1507-0473
2015
CBC NewsYellowknives Dene lose Drybones Bay diamond exploration appeal. Federal court upholds Debogorski's proposal. ( took 4 years and will still be appealed by Dene)Cbcnews.ca, June 26, 1p.Canada, Northwest TerritoriesNews item - Drybones Bay
DM1507-0474
2015
CBC News2nd De Beers Snap Lake dissolved solid limit increase OK'd by N.W.T. board. Mackenzie Valley Land and Water Board( 1,000 milligrams per litre for rest of mine's life.)Cbcnews.ca, June 25, 1p.Canada, Northwest TerritoriesNews item - De Beers
DM1508-0471
2015
CBC NewsNunavut property owners owe nearly $ 3.3 million in tax arrears. Shear Minerals owes $ 1.5 in property tax arrears on its abandoned Jericho Diamond Mine. Cbcnews.ca, July 8, 1/2p.Canada, NunavutNews item - Shear Minerals
DM1508-0472
2015
CBC NewsEkati mine expansion in NWT doesn’t need review: feds. Jay project.Cbcnews.ca, July 22, 1/4p.Canada, Northwest TerritoriesNews item - Dominion
DM1510-2002
2015
CBC NewsSnap Lake diamond mine's water licence change ok'd by N.W.T. minister.CBCnews.ca , Sept. 17, 1p.Canada, Northwest TerritoriesNews item - De Beers
DM1510-2003
2015
CBC NewsDiavik's mine's ability to recoup $ 159 million security at risk from Ekati expansion: Rio Tinto. Jay CBCnews.ca , Sept. 2, 1p.Canada, Northwest TerritoriesNews item - Rio Tinto
DM1511-2112
2015
CBC NewsWhy De Beers makes diamonds it will never sell. ( lab synthetics) Element SixCBC.ca, Oct. 8, 3p.TechnologyNews item - De Beers
DC1512-2421
2015
Centaurus Diamond Technologies Inc.Restarts final phase of R&D in revolutionary cultured diamond … MagnatekCentaurus Diamond Technologies, Inc., Nov. 5, 1p.TechnologyNews item - press release
DS1504-0188
2015
Cerantola, V., Walte, N.P., Rubie, D.C.Deformation of a crystalline olivine aggregate containing two immiscible liquids: implications for early core-mantle differentiation.Earth and Planetary Science Letters, Vol. 417, pp. 67-77.MantleCore, mantle

Abstract: Deformation-assisted segregation of metallic and sulphidic liquid from a solid peridotitic matrix is a process that may contribute to the early differentiation of small planetesimals into a metallic core and a silicate mantle. Here we present results of an experimental study using a simplified system consisting of a polycrystalline Fo90-olivine matrix containing a small percentage of iron sulphide and a synthetic primitive MORB melt, in order to investigate whether the silicate melt enhances the interconnection and segregation of FeS liquid under deformation conditions at varying strain rates. The experiments have been performed at 2 GPa, 1450?°C and strain rates between 1×10-3 s-11×10-3 s-1 to 1×10-5 s-11×10-5 s-1. Our results show that the presence of silicate melt actually hinders the migration and segregation of sulphide liquid by reducing its interconnectivity. At low to moderate strain rates the sulphide liquid pockets preserved a roundish shape, showing the liquid behavior is governed mainly by surface tension rather than by differential stress. Even at the highest strain rates, insignificant FeS segregation and interconnection were observed. On the other hand the basaltic melt was very mobile during deformation, accommodating part of the strain, which led to its segregation from the matrix at high bulk strains leaving the sulphide liquid stranded in the olivine matrix. Hence, we conclude that deformation-induced percolation of sulphide liquid does not contribute to the formation of planetary cores after the silicate solidus is overstepped. A possible early deformation enhanced core-mantle differentiation after overstepping the Fe-S solidus is not possible between the initial formation of silicate melt and the formation of a widespread magma ocean.
DS1510-1761
2014
Chakhmouradian, A.R., Cooper, M.A., Ball, N., Reguir, E.P., Medici, L., Abdu, Y., Antonov, A.A.Vladykinite, Na3Sr4(Fe2+Fe3+)Si8024: a new complex sheet silicate from peralkaline rocks of the Murun Complex, eastern Siberia, Russia.Deep-seated magmatism, its sources and plumes, Proceedings of XIII International Workshop held 2014., Vol. 2014, pp. 5-21.Russia, SiberiaDeposit - Murun

Abstract: Vladykinite, ideally Na3Sr4(Fe2+Fe3+)Si8O24, is a new complex sheet silicate occurring as abundant prismatic crystals in a dike of coarse-grained peralkaline feldspathoid syenite in the north-central part of the Murun complex in eastern Siberia, Russia (Lat. 58° 22' 48? N; Long. 119° 03' 44? E). The new mineral is an early magmatic phase associated with aegirine, potassium feldspar, eudialyte, lamprophyllite, and nepheline; strontianite (as pseudomorphs after vladykinite) and K-rich vishnevite are found in the same assemblage, but represent products of late hydrothermal reworking. Vladykinite is brittle, has a Mohs hardness of 5, and distinct cleavage on {100}. In thin section, it is colorless, biaxial negative [a = 1.624(2), b = 1.652(2), g = 1.657(2), 2Vmeas = 44(1)°, 2Vcalc = 45(1)°] and shows an optic orientation consistent with its structural characteristics (X^a = 5.1° in b obtuse, Z^c = 4.7° in b acute, Y = b). The Raman spectrum of vladykinite consists of the following vibration modes (listed in order of decreasing intensity): 401, 203, 465, 991, 968, 915, 348, 167, 129, 264, 1039, and 681 cm–1; O-H signals were not detected. The Mössbauer spectrum indicates that both Fe2+ and Fe3+ are present in the mineral (Fe3+/FeS = 0.47), and that both cations occur in a tetrahedral coordination. The mean chemical composition of vladykinite (acquired by wavelength-dispersive X-ray spectrometry and laser-ablation inductively-coupled-plasma mass-spectrometry), with FeS recast into Fe2+ and Fe3+ in accord with the Mössbauer data, gives the following empirical formula calculated to 24 O atoms: (Na2.45Ca0.56)S3.01(Sr3.81 K0.04Ba0.02La0.02Ce0.01)S3.90(Fe2+0.75Fe3+0.66Mn0.26Zn0.16Al0.12Mg0.05Ti0.01)S2.01(Si7.81Al0.19)S8.00O24. The mineral is monoclinic, space group P21/c, a = 5.21381(13), b = 7.9143(2), c = 26.0888(7) Å, b = 90.3556(7)°, V = 1076.50(5) Å3, Z = 2. The ten strongest lines in the powder X-ray diffraction pattern are [dobs in Å (I) (hkl)]: 2.957 (100) (123, 123); 2.826 (100) (117, 117); 3.612 (58) (114, 114); 3.146 (37) (120); 2.470 (32) (210, 01.10); 4.290 (30) (111, 111); 3.339 (30) (106, 115, 106); 2.604 (28) (200); 2.437 (25) (034); 1.785 (25) (21.10, 234). The structure of vladykinite, refined by single-crystal techniques on the basis of 3032 reflections with Fo > 4sFo to R1 = 1.6%, consists of tetrahedral sheets parallel to (100) and consisting of (Si8O24)16– units incorporating four-membered silicate rings and joined into five- and eight-membered rings by sharing vertices with larger tetrahedra hosting Fe2+, Fe3+, Mn, Zn, Al, Mg, and Ti. Larger cations (predominantly Na, Sr, and Ca) are accommodated in octahedral and square-antiprismatic interlayer sites sandwiched between the tetrahedral sheets. Structural relations between vladykinite and other sheet silicates incorporating four-, five-, and eight-membered rings are discussed. The name vladykinite is in honor of Nikolay V. Vladykin (Vinogradov Institute of Geochemistry, Russia), in recognition of his contribution to the study of alkaline rocks. Holotype and co-type specimens of the mineral were deposited in the Robert B. Ferguson Museum of Mineralogy in Winnipeg, Canada.
DS1512-1903
2015
Chakhmouradian, A.R., Cooper, M.A., Medici, L., Abdu, Y.A., Shelukhina, Y.S.Anzaite-(Ce), a new rare earth mineral and structure type from the Afrikanda silicocarbonatite, Kola Peninsula.Mineralogical Magazine, Vol. 79, 5, pp. 1231-1244.RussiaCarbonatite

Abstract: Anzaite-(Ce), ideally Formula Fe2+Ti6O18(OH)2, is a new, structurally complex mineral occurring as scarce minute crystals in hydrothermally altered silicocarbonatites in the Afrikanda alkali-ultramafic complex of the Kola Peninsula, Russia. The mineral is a late hydrothermal phase associated with titanite, hibschite, clinochlore and calcite replacing the primary magmatic paragenesis. The rare-earth elements (REE) (dominated by Ce), Ti and Fe incorporated in anzaite-(Ce) were derived from primary Ti oxides abundant in the host rock. Anzaite-(Ce) is brittle and lacks cleavage; the density calculated on the basis of structural data is 5.054(6) g cm-3. The mineral is opaque and grey with a bluish hue in reflected light; its reflectance values range from 15-16% at 440 nm to 13-14% at 700 nm. Its infrared spectrum shows a prominent absorption band at 3475 cm-1 indicative of OH- groups. The average chemical composition of anzaite-(Ce) gives the following empirical formula calculated on the basis of 18 oxygen atoms and two OH- groups: (Ce2.18Nd0.85La0.41Pr0.26Sm0.08Ca0.36Th0.01)S4.15Fe0.97(Ti5.68Nb0.22Si0.04)S5.94O18(OH)2. The mineral is monoclinic, space group C2/m, a = 5.290(2), b = 14.575(6), c = 5.234(2) Å, ß = 97.233(7)°, V = 400.4(5) Å3, Z = 1. The ten strongest lines in the X-ray micro-diffraction pattern are [dobs in Å (I) hkl]: 2.596 (100) 002; 1.935 (18) 170; 1.506 (14) 133; 1.286 (13) 1.11.0; 2.046 (12) 2I41; 1.730 (12) 003; 1.272 (12) 0.10.2; 3.814 (11) 1I11; 2.206 (9) 061; 1.518 (9) 172. The structure of anzaite-(Ce), refined by single-crystal techniques to R1 = 2.1%, consists of alternating layers of type 1, populated by REE (+ minor Ca) in a square antiprismatic coordination and octahedrally coordinated Fe2+, and type 2, built of five-coordinate and octahedral Ti, stacked parallel to (001). This atomic arrangement is complicated by significant disorder affecting the Fe2+, five-coordinate Ti and two of the four anion sites. The order-disorder pattern is such that only one half of these positions in total occupy any given (010) plane, and the disordered (010) planes are separated by ordered domains comprising REE, octahedral Ti and two anion sites occupied by O2-. Structural and stoichiometric relations between anzaite-(Ce) and other REE-Ti (±Nb, Ta) oxides are discussed. The name anzaite-(Ce) is in honour of Anatoly N. Zaitsev of St Petersburg State University (Russia) and The Natural History Museum (UK), in recognition of his contribution to the study of carbonatites and REE minerals. The modifier reflects the prevalence of Ce over other REE in the composition of the new mineral.
DS1508-0344
2015
Chakhmouradian, A.R., Reguir, E.P., Coueslan, C., Yang, P.Calcite and dolomite in intrusive carbonatites. II Trace element variations.Mineralogy and Petrology, in press available 17p.GlobalCarbonatite

Abstract: The composition of calcite and dolomite from several carbonatite complexes (including a large set of petrographically diverse samples from the Aley complex in Canada) was studied by electron-microprobe analysis and laser-ablation inductively-coupled-plasma mass-spectrometry to identify the extent of substitution of rare-earth and other trace elements in these minerals and the effects of different igneous and postmagmatic processes on their composition. Analysis of the newly acquired and published data shows that the contents of rare-earth elements (REE) and certain REE ratios in magmatic calcite and dolomite are controlled by crystal fractionation of fluorapatite, monazite and, possibly, other minerals. Enrichment in REE observed in some samples (up to ~2000 ppm in calcite) cannot be accounted for by coupled substitutions involving Na, P or As. At Aley, the REE abundances and chondrite-normalized (La/Yb)cn ratios in carbonates decrease with progressive fractionation. Sequestration of heavy REE from carbonatitic magma by calcic garnet may be responsible for a steeply sloping "exponential" pattern and lowered Ce/Ce* ratios of calcite from Magnet Cove (USA) and other localities. Alternatively, the low levels of Ce and Mn in these samples could result from preferential removal of these elements by Ce4+- and Mn3+-bearing minerals (such as cerianite and spinels) at increasing f(O2) in the magma. The distribution of large-ion lithophile elements (LILE = Sr, Ba and Pb) in rock-forming carbonates also shows trends indicative of crystal fractionation effects (e.g., concomitant depletion in Ba + Pb at Aley, or Sr + Ba at Kerimasi), although the phases responsible for these variations cannot be identified unambiguously at present. Overall, element ratios sensitive to the redox state of the magma and its complexing characteristics (Eu/Eu*, Ce/Ce* and Y/Ho) are least variable and in both primary calcite and dolomite, approach the average chondritic values. In consanguineous rocks, calcite invariably has higher REE and LILE levels than dolomite. Hydrothermal reworking of carbonatites does not produce a unique geochemical fingerprint, leading instead to a variety of evolutionary trends that range from light-REE and LILE enrichment (Turiy Mys, Russia) to heavy-REE enrichment and LILE depletion (Bear Lodge, USA). These differences clearly attest to variations in the chemistry of carbonatitic fluids and, consequently, their ability to mobilize specific trace elements from earlier-crystallized minerals. An important telltale indicator of hydrothermal reworking is deviation from the primary, chondrite-like REE ratios (in particular, Y/Ho and Eu/Eu*), accompanied by a variety of other compositional changes depending on the redox state of the fluid (e.g., depletion of carbonates in Mn owing to its oxidation and sequestration by secondary oxides). The effect of supergene processes was studied on a single sample from Bear Lodge, which shows extreme depletion in Mn and Ce (both due to oxidation), coupled with enrichment in Pb and U, possibly reflecting an increased availability of Pb2+ and (UO2)2+ species in the system. On the basis of these findings, several avenues for future research can be outlined: (1) structural mechanisms of REE uptake by carbonates; (2) partitioning of REE and LILE between cogenetic calcite and dolomite; (3) the effects of fluorapatite, phlogopite and pyrochlore fractionation on the LILE budget of magmatic carbonates; (4) the cause(s) of coupled Mn-Ce depletion in some primary calcite; and (5) relations between fluid chemistry and compositional changes in hydrothermal carbonates.
DS1508-0345
2015
Chakhmouradian, A.R., Reguir, E.P., Zaitsev, A.N.Calcite and dolomite in intrusive carbonatites. I Textural variastions.Mineralogy and Petrology, in press available 28p.GlobalCarbonatite

Abstract: Carbonatites are nominally igneous rocks, whose evolution commonly involves also a variety of postmagmatic processes, including exsolution, subsolidus re-equilibration of igneous mineral assemblages with fluids of different provenance, hydrothermal crystallization, recrystallization and tectonic mobilization. Petrogenetic interpretation of carbonatites and assessment of their mineral potential are impossible without understanding the textural and compositional effects of both magmatic and postmagmatic processes on the principal constituents of these rocks. In the present work, we describe the major (micro)textural characteristics of carbonatitic calcite and dolomite in the context of magma evolution, fluid-rock interaction, or deformation, and provide information on the compositional variation of these minerals and its relation to specific evolutionary processes.
DS1508-0346
2015
Chalapathi Rao, N.V., Atiullah, Kumar, A., Sahoo, S., Nanda, P., Chahong, N., Lehmann, B., Rao, K.V.S.Petrogenesis of Mesoproterozoic lamproite dykes from the Garledinne (Banganapalle) cluster, south western Cuddapah Basin, southern India.Mineralogy and Petrology, in press available 22p.IndiaLamproite

Abstract: We report mineral chemistry and whole-rock major and trace-element geochemistry for a recent find of Mesoproterozoic (~1.4 Ga) lamproites from the Garledinne (Banganapalle) cluster, south-western part of the Paleo-Mesoproterozoic Cuddapah Basin, southern India. The Garledinne lamproites occur as WNW-ESE-trending dykes that have undergone varying degree of pervasive silicification and carbonate alteration. Nevertheless, their overall texture and relict mineralogy remain intact and provide important insights into the nature of their magmas. The lamproite dykes have porphyritic to weakly porphyritic textures comprising pseudomorphed olivine macrocrysts and microphenocrysts, titanian phlogopite microphenocrysts, spinel having a compositional range from chromite to rarely magnesiochromite, Sr-rich apatite and niobian rutile. The Garledinne and other Cuddapah Basin lamproites (Chelima and Zangamarajupalle) collectively lack sanidine, clinopyroxene, potassic richterite, and titanite and are thus mineralogically distinct from the nearby Mesoproterozoic lamproites (Krishna and Ramadugu) in the Eastern Dharwar Craton, southern India. The strong correlation between various major and trace elements coupled with high abundances of incompatible and compatible trace elements imply that alteration and crustal contamination have had a limited effect on the whole-rock geochemistry (apart from K2O and CaO) of the Garledinne lamproites and that olivine fractionation played an important role in their evolution. The Garledinne lamproites represent small-degree partial melts derived from a refractory (previously melt extracted) peridotitic mantle source that was subsequently metasomatised (enriched) by carbonate-rich fluids/melts within the garnet stability field. The involvement of multiple reservoirs (sub-continental lithospheric mantle and asthenosphere) has been inferred in their genesis. The emplacement of the Garledinne lamproites is linked to extensional events, across the various Indian cratons, related to the break-up of the Proterozoic supercontinent of Columbia.
DS1509-0389
2015
Chalapathi Rao, N.V., Dongre, A., Wu, F-Y., Lehmann, B.A Late Cretaceous ( ca.90Ma) kimberlite event in southern India: implication for sub-continental lithospheric mantle evolution and diamond exploration. WajrakarurGondwana Research, in press available 12p.IndiaDeposit - Timmasamudram
DC1505-1428
2015
Chalice Gold Mines LimitedWebb diamond project update. ( Meteoric Resources Limited press release)Chalice Gold Mines Limited, Mar. 27, 1p.AustraliaNews item - press release
DS1506-0258
2015
Chapin, M.,Pardieu, V., Lucas, A.Mozambique: a ruby discovery for the 21st. Century. MontepuezGems & Gemology, Vol. 51, 1, pp. 44-54.Africa, MozambiqueDeposit - ruby
DS1504-0189
2015
Chapman, J.Why aren't all natural diamonds larger than 10 carats - they've had millions of years to grow.Vancouver Kimberlite Cluster, Mar. 17, 1p. AbstractTechnologyDiamond morphology
DS1504-0190
2015
Chapman, J.Chromism in pink diamonds.The Australian Gemmologist, Vol. 25, 8, pp. 268-271.TechnologyDeposit - Argyle
DS1511-1828
2004
Chapman, J.G., Boxer, G.L.Size distribution analyses for estimating grade and value.Lithos, Vol. 76, pp. 369-375. Available pdfTechnologyMicrodiamonds - responses

Abstract: Analysing the size frequency distributions (SFDs) of both micro diamonds and macro diamonds from primary deposits shows that the distributions are continuous across all sizes and that there are two regions of different character with a transition about 1-2 mm. Using log axes, the frequency curve is linear for the smaller sizes allowing slope and intercept parameters to be determined which are less ambiguous than stone counts and ratios of macro to micro populations that are generally reported. Modelling a diamond population that has undergone removal of a uniform thickness of the outer layer transforms a linear frequency curve into a quadratic form, which is also the form of the frequency curve for macro diamonds. Diamonds grown synthetically also display a linear distribution across a smaller fraction of their size distribution curve.
DS1510-1762
2015
Cheirsirikul, S., Jesen, S., Hruanun, C.The MSM diamond device for direct and indirect X-ray detection.2015 IEEE 10th International Conference on Nan/Micro Engineered and Molecular Systems, NEMS 2015, pp. 372-374.TechnologyX-ray dectector

Abstract: Development synthesizing diamond film on silicon substrate was processed by Hot Filament Chemical Vapor Deposition (HFCVD). The gas processes using of H2 and CH4 to produce intrinsic diamond and MSM device constructed on the diaphragm of diamond film. Schottky junctions on the top and the lower diaphragm were produced by aluminum metal. After that, the result of detecting a direct and indirect X-ray of MSM diamond was satisfactory because it could respond along with increasing of X-ray intensity. The X-ray expose time of indirect expose by BaF2 scintillator faster more than direct expose.
DS1502-0050
2015
Chen, M., Tian, W.Surface and mantle expression of the Early Permian Tarim mantle plume.Economic Geology Research Institute 2015, Vol. 17,, # 1147, 1p. AbstractChinaPeridotite, xenoliths

Abstract: The mantle process during the Early Permian Tarim plume event is revealed by flood basalt and mantle xenoliths. Permian Tarim flood basalts have typical two pulses' eruption. The first pulse of the Tarim flood basalt was erupted at 291-290Ma, characterized by OIB-like Zr/Nb (~5.83), Nb/La and Ce/Pb ratios, and PUM-like initial 187Os/188Os ratios (0.1308-0.1329). They're plotted along a 290±11Ma isochron, implying a pristine "plume mantle" source. The second pulse of the Tarim flood basalt was erupted at 283-281 Ma, with Zr/Nb (~13.6), Nb/La and Ce/Pb ratios similar or close to the lower crust and initial 187Os/188Os ratios (0.1743~19.6740) that deviated from the ~290 Ma isochron line, indicative of significant crustal assimilation. Mantle-derived peridotite and pyroxenite xenoliths hosted in Cenozoic alkali basalts (~20 Ma) are found in the Xikeer, western Tarim Block. Based on their petrographic and geochemical characteristics, peridotite xenoliths can be divided into three groups. Group 1 peridotites, with the presence of the high Mg-number of olivines (91-93) and spinel-pyroxenes clusters, experienced high-degree melt extraction (~17% fractional melting) from garnet- to spinel-stable field. Groups 2 and 3 peridotites, characterized by the clinopyroxenes with spoon-shaped and highly fractionated REE patterns respectively, underwent extensive silicate melt metasomatism at low melt/rock ratios (15) and that the host basanite is incapable of being the metasomatic agent. The Re-Os isotopic systematics of the Xikeer peridotites and pyroxenites yield an isochron of 290±11 Ma, virtually identical to the age of Tarim flood basalts. Their PUM-like Os initial ratios and convecting mantle-like É?Nd(t=290 Ma) strongly suggest that the Xikeer mantle xenoliths derive from the plume mantle. We propose that the Xikeer xenolith suite recorded mantle 'auto-refertilization' process, i.e., they may have been initially formed by melt extraction from the convecting mantle and, shortly after, was refertilized by plume melts during the Early Permian.
DS1502-0051
2015
Chen, T., Gwanmesia, G.D., Wang, X., Zou, Y., Liebermann, R.C., Michaut, C., Li, B.Anomalous elastic properties of coesite at high pressure and implications for the upper mantle X-discontinuity.Earth and Planetary Science Letters, Vol. 412, pp. 42-51.MantleCoesite

Abstract: Compressional and shear wave velocities of coesite have been measured using ultrasonic interferometry in a multi-anvil apparatus up to 12.6 GPa at room temperature for the first time. While the P wave velocity increases continuously with pressure, the S wave exhibits an anomalous softening and the velocity decreases continuously with pressure. Finite strain analysis of the data yielded KS0=103.6(4) GPaKS0=103.6(4) GPa, G0=61.6(2) GPaG0=61.6(2) GPa and View the MathML sourceK0'=2.9(1), View the MathML sourceG0'=0.3(1) for the bulk and shear moduli and their pressure derivatives, respectively. The anomalous elastic behavior of coesite results in large velocity and impedance contrasts across the coesite–stishovite transition, reaching ~39% and ~48% for P and S wave velocity contrasts, and ~70% and 78% for P and S wave impedance contrasts, respectively, at pressure ~8 GPa, with P and S wave velocity perturbations showing no apparent dependence on depths (i.e., View the MathML sourcedln?V(PorS)/dh~0) within 8–12 GPa. These unusually large contrasts and depth independent characteristics render the transition between the two silica polymorphs one of the most plausible candidates for the cause of the seismically observed X-discontinuity. The current P and S wave velocity perturbation dependences on the SiO2 content, d(ln?VP)/d(SiO2)~0.43 (wt%)-1d(ln?VP)/d(SiO2)~0.43 (wt%)-1 and d(ln?VS)/d(SiO2)~0.60 (wt%)-1d(ln?VS)/d(SiO2)~0.60 (wt%)-1, can serve as a geophysical probe to track ancient subducted eclogite materials to gain insights on the geodynamics of the mantle.
DS1512-1904
2015
Chen, W., Leblanc, S.G., White, H.P., Milkovic, B., O'Keefe, H., Croft, B., Gunn, A., Boulanger, J.Caribou relevant environmental changes around the Ekati diamond mine measured in 2015.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 24.Canada, Northwest TerritoriesDeposit - Ekati

Abstract: How would a large open pit mine on caribou range (e.g., the Ekati Diamond Mine in the Bathurst caribou’s summer range) have influenced caribou? A traditional knowledge study on the cumulative impacts on the Bathurst caribou herd qualitatively described how mining activities might have influenced the herd (Mackenzie et al. 2013): caribou migration routes deflected away from the mines probably due to seeing mining activities or hearing the noises; and skinny caribou or abnormal smells and materials in caribou meat, liver, or the hide linings probably related to changes in caribou forage and quality of water and air. In other words, the potential influences of mining operations on caribou were most likely through altering what caribou can see, hear, smell (e.g., dusts and fine particle matter < 2.5 ?m (PM2.5) in the air, and from acidity in the soil), and taste (e.g., dust on foliage, vegetation composition change). Boulanger et al. (2012) estimated the size of a zone of influence (ZOI) of the Ekati-Diavik mining complex in the Bathurst caribou summer range, using caribou presence dataset. They also explored the mechanisms of ZOI using the spatial distribution of the total suspended particles, which was simulated with an atmospheric transport and dispersion model (Rescan, 2006). While these studies have added to our understanding of the possible impacts of mining operations on caribou, knowledge gaps remain. One outstanding gap is the lack of direct measurements about the caribou relevant environmental changes caused by mining operations. For example, exactly from how far away can caribou clearly see the vehicles driving on a mining road, or the buildings and the elevated waste piles in a camp? From how far away might caribou hear the noise caused by mining operations? To what spatial extent had the dusts and PM2.5 from mining operations influenced the tundra ecosystems? And how the dusts and PM2.5 from mining operations might have influenced caribou forage quality? Potentially these questions can be answered by in-situ measurements and satellite remote sensing. For example, studies have showed that it is possible to remotely sense PM2.5 distribution using twice-daily MODIS data at a spatial resolution of 1 km (Lyapustin et al., 2011; Chudnovsky et al., 2013; Hu et al., 2014). The objective of this study is thus to quantitatively measure these changes around the Ekati Diamond Mine, by means of in-situ surveys and satellite remote sensing. We conducted field surveys at more than 100 sites around the Ekati Diamond Mine during August 14-23, 2015, a collaborative effort of the NWT CIMP project entitled “Satellite Monitoring for Assessing Resource Development’s Impact on Bathurst Caribou (SMART)”, and the Dominion Diamond Ekati Corporation. In this presentation, we will report preliminary results and lessons learned from our first year’s study.
DS1508-0347
2015
Chepurov, A.A., Pokhilenko, N.P.Experimental estimation of the kimberlite melt velosity. ( Nyurbinskaya mentioned)Doklady Earth Sciences, Vol. 462, 2, pp. 592-595.TechnologyPetrology - geodynamic model
DC1510-2337
2015
CMKM Diamonds Inc.CMKM defendants see Spooner plead guilty. Stockwatch, Sept. 10, 2p.United States, NevadaNews item - CMKM
DM1508-0478
2015
CNNPark visitor unearths 8.52 carat diamond in Arkansas. Esperanza DiamondCNN, June 27, 1p.United States, ArkansasNews item - Crater of Diamonds
DM1508-0479
2015
CNNRains wash out gems, lives in Gujarat diamond district.CNN, June 27, 1/2p.IndiaNews item - Gujarat
DS1511-1829
2015
Coblentz, D., Van Wijk, J., Richardson, R.M., Sandiford, M.The upper mantle geoid: implications for continental structure and the intraplate stress field.Geological Society of America Special Paper, No. 514, pp. SPE514-13.MantleGeophysics - seismics

Abstract: We use the fact that geoid anomalies are directly related to the local dipole moment of the density-depth distribution to help constrain density variations within the lithosphere and the associated tectonic stresses. The main challenge with this approach is isolating the upper mantle geoid contribution from the full geoid (which is dominated by sources in the lower mantle). We address this issue by using a high-pass spherical harmonic filtering of the EGM2008-WGS84 geoid to produce an "upper mantle" geoid. The tectonic implications of the upper mantle are discussed in terms of plate tectonics and intraplate stresses. We find that globally there is about a 9 meter geoid step associated with the cooling oceanic lithosphere that imparts a net force of ~2.5x1012 N/m in the form of "ridge push" - a magnitude that is consistent with 1-d models based on first-order density profiles. Furthermore, we ind a consistent 6 meter geoid step across passive a continental margin which has the net effect of educing the compressive stresses in the continents due to the ridge force. Furthermore, we use the pper mantle geoid to reevaluate the tectonic reference state which previously studies estimated using n assumption of Airy-based isostasy. Our evaluation of the upper mantle geoid confirms the near quivalence of the gravitational potential energy of continental lithosphere with an elevation of about 750 meters and the mid-ocean ridges. This result substantiates early conclusions about the tectonic reference state and further supports the prediction that continental regions are expected to be in a slightly extensional state of stress.
DS1503-0137
2015
Cohen, R.Missing link in metal physics explains Earth's magnetic field.gl.ciw.edu, Jan. 28, 1p.TechnologyMagnetics
DS1504-0191
2015
Comin-Chiaramonti, P., Gomes, C.B., De Min, A., Ernesto, M., Gasparon, M.Magmatism along the high Paraguay River at the border of Brazil and Paraguay: a review and new constraints on emplacement ages.Journal of South American Earth Sciences, Vol. 58, March pp. 72-81.South America, Paraguay, BrazilGeochronology

Abstract: The magmatic rocks from Alto Paraguay (High Paraguay River extensional lineament), western Apa craton, mainly consist of several major circular alkaline complexes and some rhyolitic domes and ignimbrites. The former are characterized by intrusive Na-alkaline rock-types (nepheline syenites and syenites and effusive equivalents) topped by lava flows and ignimbrites. Two main evolved suites were defined using petrochemical and Sr- isotope data: an agpaitic suite in the north and a miaskitic suite in the south. The domes of subalkaline rhyolitic lavas and ignimbrites occur to the north of the alkaline complexes, along the Paraguay River, near the town of Fuerte Olimpo. The emplacement ages of the alkaline complexes were constrained using the K-Ar, Ar-Ar, Rb-Sr and Sm-Nd dating methods on whole rocks and/or mineral separates (amphibole, alkali feldspar and biotite). Ages are quite variable (Upper Permian to Middle Triassic), with average K-Ar and Ar-Ar ages of 248.8 ± 4.8 and 241.8 ± 1.1 Ma, respectively, and Rb-Sr and Sm-Nd age data giving best values from 248 ± 4 to 244 ± 27 Ma and from 256 ± 3 to 257 ± 3 Ma, respectively. In contrast, the Fuerte Olimpo volcanics show a Mesoproterozoic age (1.3 Ga, K-Ar and Ar-Ar radiometric methods; and 1.42 ± 0.24 to 1.30 ± 0.03 Ga, Rb-Sr and Sm-Nd methods, respectively). Rb-Sr systematics (87Sr/86Sr initial ratios = 0.7038) highlight a relatively "primitive" character of the Na-alkaline magmatic source(s), in contrast with the "crustal" values (87Sr/86Sr initial ratio ~ 0.7105) of the Fuerte Olimpo rhyolites. Thus, magmatism in the Alto Paraguay area is related to two extensional events: a younger event corresponding to the Permian-Triassic alkaline rocks, and an older event connected to the Precambrian volcanic acidic rocks.
DC1505-1429
2015
Commerce Resources CorporationCommerce Resources completes 22 drill holes at the Ashram rare earth deposit.Commerce Resources Corporation, Apr. 15, 2p.Canada, QuebecNews item - press release
DC1505-1430
2015
Commerce Resources CorporationCompletes floatation pilot plant for Ashram rare earth deposit.Commerce Resources Corporation, Apr. 20, 2p.Canada, British ColumbiaNews item - press release
DS1510-1763
2015
Condie, B.Scientists create record pressure in a lab - twice that of Earth's core. Osmium sample.blog. cosmos magazine.com, Aug. 25, 1p.TechnologyOsmium
DS1506-0259
2015
Condie, K., Davaille, AsterUpstairs - downstairs: supercontinents and large igneous provinces, are they related?International Geology Review, Vol. 57, 11-12, pp. 1341-1348.MantleSupercontinents

Abstract: There is a correlation of global large igneous province (LIP) events with zircon age peaks at 2700, 2500, 2100, 1900, 1750, 1100, and 600 and also probably at 3450, 3000, 2000, and 300?Ma. Power spectral analyses of LIP event distributions suggest important periodicities at 250, 150, 100, 50, and 25?million years with weaker periodicities at 70-80, 45, and 18-20?Ma. The 25?million year periodicity is important only in the last 300?million years. Some LIP events are associated with granite-forming (zircon-producing) events and others are not, and LIP events at 1900 and 600?Ma correlate with peaks in craton collision frequency. LIP age peaks are associated with supercontinent rifting or breakup, but not dispersal, at 2450-2400, 2200, 1380, 1280, 800-750, and =200?Ma, and with supercontinent assembly at 1750 and 600?Ma. LIP peaks at 2700 and 2500?Ma and the valley between these peaks span the time of Neoarchaean supercraton assemblies. These observations are consistent with plume generation in the deep mantle operating independently of the supercontinent cycle and being controlled by lower-mantle and core-mantle boundary thermochemical dynamics. Two processes whereby plumes can impact continental assembly and breakup are (1) plumes may rise beneath supercontinents and initiate supercontinent breakup, and (2) plume ascent may increase the frequency of craton collisions and the rate of crustal growth by accelerating subduction.
DS1509-0390
2015
Cooper, C.M.Puzzling the pieces - supercontinent at depth.Geology, Vol. 43, 9, pp. 847-848.GlobalPlate reconstructions

Abstract: Alfred Wegener famously argued that the seemingly puzzle piece–like fit of the Atlantic coastlines was not a mere coincidence, but rather one line of evidence proving that the continents were once arranged as a single, coherent supercontinent (Wegener, 1912,1920). This puzzle piece observation eventually launched a revolution that changed our understanding of the Earth from its deep interior to evolutionary processes. Often, however, we think of the supercontinent puzzle in a two-dimensional sense, neglecting to include or consider how variations of the thickness of the puzzle pieces might also be at play. How do the puzzle pieces fit together at depth, and is there more to learn by including lithospheric thickness in our plate reconstructions? Would thinking three-dimensionally in our plate reconstructions help resolve some of the outstanding questions about supercontinents, continental deformation, and the lithosphere in general? This is the motivation of new research by McKenzie et al. (2015, p. 783 in this issue of Geology).
DS1512-1905
2015
Cordier, C., Sauzeat, L., Arndt, N.T., Boullier, A-M., Batanova, V., Barou, F.Metasomatism of the lithospheric mantle immediately precedes kimberlite eruption: new evidence from olivine composition and microstructures.Journal of Petrology, Vol. 56, 9, pp. 1775-1796.TechnologyOlivine, metasomatism

Abstract: Most kimberlites contain abundant dunitic nodules. These are centimetre-sized, rounded and multi-grained assemblages of xenocrystic olivine with a wide range of compositions (Fo83 to Fo94). The absence of orthopyroxene and other mantle minerals and the range of olivine compositions have been attributed to reaction between mantle peridotite and (proto)kimberlitic fluid or melt, but the timing of the reaction is a subject of debate. In a kimberlite from the Kangamiut region of Greenland, nodule cores are surrounded by fine-grained outer margins with near-constant Fo contents (~Fo88) but highly variable minor element contents (e.g. 500-2500 ppm Ni). These margins crystallized from the kimberlite melt and we show that their compositions can be explained by crystallization of olivine alone, if a high partition coefficient for Ni between melt and olivine (DNi > 20) is assumed. Orthopyroxene assimilation is not required, removing the constraint that its dissolution occurred during ascent of the kimberlite magma. Within some nodules, in addition to the usual core-to-margin gradients, we observe asymmetric compositional changes (variable Fo but near-constant minor element contents) across mobile grain boundaries. These changes document fluid percolation at the grain scale that occurred during dynamic recrystallization in the deforming lithospheric mantle. We note that chemical gradients associated with mobile grain boundaries are observed in olivines that cover the entire compositional range of the nodules, and propose that fluid-assisted dynamic recrystallization took place in dunite that was already compositionally heterogeneous. Reaction between peridotite and protokimberlitic melt or fluid and dissolution of orthopyroxene thus occurred within the lithospheric mantle, immediately (a few days) prior to the ascent of the kimberlite melt and the entrainment of the dunite nodules. We propose that the grain boundary zones probably mimic, at a fine scale, the fluid-peridotite interaction that caused, at a larger scale, orthopyroxene dissolution and formation of compositionally diverse olivine in kimberlites.
DS1509-0391
2015
Cornah, A., Machaka, E.Integration of imprecise and biased data into mineral resource estimates.South African Institute of Mining and Metallurgy, Vol. 115, June pp. 523-531.GlobalResource estimation, kriging not specific to diamonds

Abstract: Mineral resources are typically informed by multiple data sources of varying reliability throughout a mining project life cycle. Abundant data which are imprecise or biased or both (‘secondary data’) are often excluded from mineral resource estimations (the ‘base case’) under an intuitive, but usually untested, assumption that this data may reduce the estimation precision, bias the estimate, or both. This paper demonstrates that the assumption is often wasteful and realized only if the secondary data are naïvely integrated into the estimation. A number of specialized geostatistical tools are available to extract maximum value from secondary information which are imprecise or biased or both; this paper evaluates cokriging (CK), multicollocated cokriging (MCCK), and ordinary kriging with variance of measurement error (OKVME). Where abundant imprecise but unbiased secondary data are available, integration using OKVME is recommended. This re-appropriates kriging weights from less precise to more precise data locations, improving the estimation precision compared to the base case and to Ordinary Kriging (OK) of a pooled data-set. If abundant secondary data are biased and imprecise, integration through CK is recommended as the biased data are zero-sum weighted. CK consequently provides an unbiased estimate with some improvement in estimation precision compared to the base case.
DS1512-1906
2015
Counts, B., Power, M.Proxima Diamonds Corp.: exploring for diamonds in the fertile Slave craton.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 33.Canada, Northwest TerritoriesProspect - Sancy

Abstract: Proxima Diamonds Corp. is a private Canadian diamond exploration company exploring diamond targets in the heart of the diamond producing region of the Slave Geological Province. The company holds 17 target-rich properties that were selected based on a review of publicly available data, a proprietary kimberlite indicator mineral sample database and a wealth of experience exploring for diamonds in Canada's north. Focused kimberlite indicator mineral (KIM) sampling conducted by Proxima in 2014 identified a potential source area on the Sancy Property, located near the northern boundary of the Ekati Diamond Mine. Follow-up ground geophysical surveys completed over the area in spring 2015 have returned compelling results. Ground gravity, total magnetic field and capacitively coupled resistivity surveys identified a large, new target approximately 300 m from the diamondiferous T-10 kimberlite pipe. On this and other Proxima properties, focused KIM till sampling is defining likely source areas which will be surveyed with ground geophysical methods this winter.
DS1503-0138
2014
Cowing, M.D.Objective diamond clarity grading.The Journal of Gemmology, Vol. 34, 4, pp. 316-332.TechnologyMethodology and consistency
DS1503-0139
2015
Cowing, M.D.Grading diamond clarity objectively.Book - self published, michaelgem @gmail.com, Book availableTechnologyDiamond grading
DS1506-0260
2015
Crater of Diamonds State ParkPark visitor from Arkansas finds 3.69 carat white, teardrop-shaped diamond yesterday ( April 23) at Arkansas Crater of Diamonds State Park. Hallelujah nameCrater of Diamonds State Park, Apr. 23, 2p.United States, ArkansasCrater of Diamonds
DM1501-0480
2014
Creamers Mining WeeklyRio Tinto on path to sustainable increased shareholder returns.Creamers Mining Weekly, Dec. 4, 1/4p.GlobalNews item - Rio Tinto
DM1501-0481
2014
Creamers Mining WeeklyRio Tinto diamond bet adds sparkle to junior miner's prospects. Creamers Mining Weekly, Dec. 4, 1/4p.CanadaNews item - Rio Tinto
DM1501-0482
2014
Creamers Mining WeeklyDiamonds look to set to do well in 2015 - Investec.Creamers Mining Weekly, Dec. 5, 1/4p.GlobalNews item - prices
DM1501-0483
2014
Creamers Mining WeeklyFirst diamonds exported from Baoule trial mining.Creamers Mining Weekly, Dec. 5, 1/4p.Africa, GuineaNews item - Stellar
DM1501-0484
2014
Creamers Mining WeeklyStrike ends at DiamondCorp's Lace mine, workers to return on Monday.Creamers Mining Weekly, Dec. 5, 1/4p.Africa, South AfricaNews item - DiamondCorp
DM1501-0485
2014
Creamers Mining WeeklyParagon raises Lb257,000Creamers Mining Weekly, Dec. 5, 1/4p.Africa, LesothoNews item - Paragon
DM1501-0486
2014
Creamers Mining WeeklyStellar secures sufficient funds for working needs until first diamond sales.Creamers Mining Weekly, Dec. 11, 1/4p.Africa, GuineaNews item - Stellar
DM1501-0487
2014
Creamers Mining WeeklyDespite sagging grades, prices, Rockwell Diamonds reports record Q3 revenue.Creamers Mining Weekly, Dec. 16, 1/4p.Africa, South AfricaNews item - Rockwell
DM1502-0488
2015
Creamers Mining WeeklyDe Beers launches hub for entrepreneurs in Cape Town. De Beers Marine Zimele Business Hub.Creamers Mining Weekly, Jan. 8, 1/4p.Africa, South AfricaNews item - DBCM
DM1502-0489
2015
Creamers Mining WeeklyRio Tinto to invest $ 500 m in diamond project in India.Creamers Mining Weekly, Jan. 12, 1/4p.India, Madhya PradeshNews item - Rio Tinto
DM1502-0490
2015
Creamers Mining WeeklyRockwell boosts carat sales as recovery of large diamonds falters.Creamers Mining Weekly, Jan. 13, 1/4p.Africa, South AfricaNews item - Rockwell
DM1502-0491
2015
Creamers Mining WeeklyThe low oil price is expected to benefit the diamond business. De Beers CEO Phillippe Mellier.Creamers Mining Weekly, Jan. 21, 1/4p.GlobalNews item - De Beers
DM1503-0492
2015
Creamers Mining WeeklyGem Diamonds warns of possible price softening in early 2015. ElphickCreamers Mining Weekly, Jan. 27, 2p.Africa, BotswanaNews item - Gem Diamonds
DM1503-0493
2015
Creamers Mining WeeklyDiamond demand on the rise.Creamers Mining Weekly, Feb. 10, 1p.GlobalNews item - demand
DM1503-0494
2015
Creamers Mining WeeklyColoured gemstones coming into their own after being outshone by diamonds for decades.Creamers Mining Weekly, Feb 12, 1/4p.GlobalNews item - gemstones
DM1503-0495
2015
Creamers Mining WeeklyConstruction of De Beers Letlhakane tailings treatment plant.Creamers Mining Weekly, Feb. 20, 1/2p.Africa, BotswanaNews item - De Beers
DM1503-0496
2015
Creamers Mining WeeklyBotswana Diamonds with partner Alrosa focusing on Orapa area. Siesko and Future Creamers Mining Weekly, Feb. 20, 1/2p.Africa, BotswanaNews item - Botswana Diamonds, Alrosa
DM1503-0497
2015
Creamers Mining WeeklyLucara Diamond Corp declares special dividend on strong 2014 performance. KaroweCreamers Mining Weekly, Feb. 22, 1/4p.Africa, BotswanaNews item - Lucara
DM1503-2465
2015
Creamers Mining WeeklyMountain Province Diamonds starts C$95 m rights offering to fund cost overrun facility.Creamers Mining Weekly, Feb.22, 1/4p.Canada, Northwest TerritoriesNews item - Mountain Province
DM1504-0498
2015
Creamers Mining WeeklyAim listed diamond explorer Botswana Diamonds has shifted its 2015 focus to three licence areas covering more than 1000 km2 in the diamond province of Orapa, Botswana. GopeCreamers Mining Weekly, Feb. 20, 2p.Africa, BotswanaNews item - Botswana Diamonds
DM1504-0499
2015
Creamers Mining WeeklyDiamcor earnings drop 36%y/y. Krone-EndoraCreamers Mining Weekly, Feb. 27, 1/4p. Africa, South AfricaNews item - Diamcor
DM1504-0500
2015
Creamers Mining WeeklyConstruction on Letlhakane tailings expansion to start soon.Creamers Mining Weekly, Feb 25, 1p.Africa, BotswanaNews item - Debswana
DM1504-0501
2015
Creamers Mining WeeklyRio Tinto discloses tax payments to governments. Creamers Mining Weekly, Mar. 18, 1/4p.GlobalNews item - Rio Tinto
DM1504-0502
2015
Creamers Mining WeeklyEarly signs of another good year for diamond jewellery - De Beers.Creamers Mining Weekly, Mar. 20, 1/4p.GlobalNews item - De Beers
DM1504-0503
2015
Creamers Mining WeeklyGlobal diamond jewellery demand hits record $ 81 bln.Creamers Mining Weekly, Mar. 20, 1/4p.GlobalNews item - De Beers
DM1504-0504
2015
Creamers Mining WeeklySA junior in partnership to reopen Ghana diamond mine. Limoz Resources and Great Consolidated Diamond Ghana Limited. AkwatiaCreamers Mining Weekly, Mar. 20, 1p.Africa, GhanaNews item - Limoz
DM1504-0505
2015
Creamers Mining WeeklyFaltering Mbada resorts to digging conglomerate diamonds. MarangeCreamers Mining Weekly, Mar. 19, 1/2p.Africa, ZimbabweNews item - Mbada
DM1504-0506
2015
Creamers Mining WeeklyNew mining legislation to empower Indian provinces ( have to adhere to federal guidelines).Creamers Mining Weekly, Mar. 25, 1/4p.IndiaNews item - legal
DM1505-0507
2015
Creamers Mining WeeklyDe Beers starts three year global sightholder sales contracts.Creamers Mining Weekly, Mar. 31, 1/4p.GlobalNews item - De Beers
DM1505-0508
2015
Creamers Mining WeeklyNorton Rose Fulbright advises on $ 370 m financing of world's largest new diamond project. Gahcho KueCreamers Mining Weekly, Apr. 10, 1/4p.Canada, Northwest TerritoriesNews item - Mountain Province
DM1505-0509
2015
Creamers Mining WeeklyDebswana to cap output due to slow demand. Creamers Mining Weekly, Apr. 10, 1/4p.Africa, BotswanaNews item - Debswana
DM1505-0510
2015
Creamers Mining WeeklyFlawless 100 carat diamond sells for $ 22.1 million at N.Y. auction. Creamers Mining Weekly, Apr. 22, 1/4p.Africa, South AfricaNews item - diamond notable
DM1505-0511
2015
Creamers Mining WeeklyRio Tinto's Zimbabwe diamond production falls 42% in Q1. MurowaCreamers Mining Weekly, Apr. 21, 1/4p.Africa, ZimbabweNews item - Rio Tinto
DM1506-0512
2015
Creamers Mining WeeklyZimbabwe suspends tax on diamond sales - letter to IMF.Creamers Mining Weekly, Apr. 30, 1/4p.Africa, ZimbabweNews item - legal
DM1506-0513
2015
Creamers Mining WeeklyWorld Bourses prepare to confront diamond troubles at global gathering. Creamers Mining Weekly, Apr. 30, 1/4p.GlobalNews item - Bourses
DM1506-0514
2015
Creamers Mining WeeklyLace mine on target for mid-year start up.Creamers Mining Weekly, Apr. 30, 1/4p.Africa, South AfricaNews item - DiamondCorp
DM1506-0515
2015
Creamers Mining WeeklyBlueRock completes upgrade of Kareevlei plant, resumes commercial mining.BlueRock Diamonds Plc., May 19, 1/4p.Africa, South AfricaNews item - BlueRock
DM1506-0516
2015
Creamers Mining WeeklyNew mineral development strategy seeks to maintain Ontario's pole position. Creamers Mining Weekly, May 20, 1p.Canada, OntarioNews item - legal
DM1506-0517
2015
Creamers Mining WeeklyTrans Hex readies or hefty FY earninsg jump. Creamers Mining Weekly, May 25, 1/4p.Africa, South AfricaNews item - Trans Hex
DM1506-0518
2015
Creamers Mining WeeklyMining to kick off at Lace mine ahead of schedule in H2.Creamers Mining Weekly, May 26, 1/4p.Africa, South AfricaNews item - DiamondCorp
DM1507-0519
2015
Creamers Mining WeeklyLucapa to sign earthmoving deal, lists on Frankfurt Stock Exchange 28 May. LuloCreamers Mining Weekly, May 28, 1p.Africa, AngolaNews item - Lucapa
DM1507-0520
2015
Creamers Mining WeeklyIndia makes provisions for composite mining licences.Creamers Mining Weekly, June 3, 1/4p.IndiaNews item - legal
DM1507-0521
2015
Creamers Mining WeeklyJunior miners perceive Botswana as best investment destination.Creamers Mining Weekly, June 3, 1/4p.Africa, BotswanaNews item - legal
DM1507-0522
2015
Creamers Mining WeeklySouth Africa's geoscience desperately underfunded - Nedbank Capital comment.Creamers Mining Weekly, June 5, 1/4p.Africa, South AfricaNews item - DMR
DM1507-0523
2015
Creamers Mining WeeklyPioneering Botswana diamond circuit set for design run this month. KaroweCreamers Mining Weekly, June 9, 2p.Africa, BotswanaNews item - Lucara
DM1507-0524
2015
Creamers Mining WeeklyMining subtracting from Botswana's economic growth - economist.Creamers Mining Weekly, June 9, 1/2p.Africa, BotswanaNews item - economics
DM1507-0525
2015
Creamers Mining WeeklyBotswana diamond beneficiation hits rough patch.Creamers Mining Weekly, June 9, 1/2p.Africa, BotswanaNews item - Diamond Hub
DM1507-0526
2015
Creamers Mining WeeklyLesotho govt processing sale of Mothae diamond stake.Creamers Mining Weekly, June 9, 1/4p.Africa, LesothoNews item - Paragon
DM1507-0527
2015
Creamers Mining WeeklyDiamond miners show potential; as 4 declare dividends in last year. Alrosa, Dominion, Gem, Petra.Creamers Mining Weekly, June 12, 3p.GlobalNews item - dividends
DM1507-0528
2015
Creamers Mining WeeklyAlrosa does not see recovery in diamond prices this year.Creamers Mining Weekly, June 16 1/4p.RussiaNews item - Alrosa
DM1507-0529
2015
Creamers Mining WeeklyDiamond industry in the midst of 'complicated times'. Blom.Creamers Mining Weekly, June 15, 1/4p.GlobalNews item - economics
DM1507-0530
2015
Creamers Mining WeeklyDiamondCorp offers 21 m shares to raise 2 million pounds. LaceCreamers Mining Weekly, June 8, 1/4p.Africa, South AfricaNews item - DiamondCorp
DM1507-0531
2015
Creamers Mining WeeklyUncertain future for global diamond trade as profits vanish.Creamers Mining Weekly, June 25, 1/4p.GlobalNews item - economics
DM1507-0532
2015
Creamers Mining WeeklyRockwell to focus on production profile as Saxendrift output decreases.Creamers Mining Weekly, June 25, 1/4p.Africa, South AfricaNews item - Rockwell
DM1507-0533
2015
Creamers Mining WeeklyRio Tinto to sell stakes in Zim diamond, coal assets. MuroweCreamers Mining Weekly, June 25, 1/4p.Africa, ZimbabweNews item - Rio Tinto
DM1508-0534
2015
Creamers Mining WeeklyKimberley Diamonds secures debt finance for Botswana mine. From China based auction house Zhejiang Huitong. LeralaCreamers Mining Weekly, June 30, 1p.Africa, BotswanaNews item - Kimberley
DM1508-0535
2015
Creamers Mining WeeklyDiamondCorp raises 5 million lbs oversubscribed offer. LaceCreamers Mining Weekly, July 6, 1/4p.Africa, South AfricaNews item - DiamondCorp
DM1508-0536
2015
Creamers Mining WeeklyMadagascar to pass mining, petroleum bills in October - Minister.Creamers Mining Weekly, July 10, 1/4p.Africa, MadagascarNews item - legal
DM1508-0537
2015
Creamers Mining WeeklyKimberley gets go ahead for Lerala. Creamers Mining Weekly, July 20, 1/4p.Africa, BotswanaNews item - Kimberley Diamonds
DM1508-0538
2015
Creamers Mining WeeklyAmec launch of the UNCOVER Roadmap. …for greenfield exploration support.Creamers Mining Weekly, July 21, 1p.AustraliaNews item - AMEC
DM1509-0539
2015
Creamers Mining WeeklyDiamond miner De Beers Group has renewed gas and welding company Afrox contract ( Venetia)Creamers Mining Weekly, Aug. 28, 1/4p.Africa, South AfricaNews item - De Beers
DM1510-2004
2015
Creamers Mining WeeklyDiamond, gold worth Rand 2 Million bust at Beitbridge.Creamers Mining Weekly, Sept. 4, 1/4p.Africa, South Africa, Democratic Republic of CongoNews item - legal
DM1510-2005
2015
Creamers Mining WeeklyBotswana's Debswana cuts diamond production due to market downturn.Creamers Mining Weekly, Sept. 12, 1/4p.Africa, BotswanaNews item - Debswana
DM1510-2006
2015
Creamers Mining WeeklyBotswana Diamonds advances work at Orapa.Creamers Mining Weekly, Sept. 12, 1/4p.Africa, BotswanaNews item - Botswana Diamonds, Alrosa
DM1510-2007
2015
Creamers Mining WeeklyLucapa secures financing for Angolan expansion.Creamers Mining Weekly, Sept. 14, 1/2p.Africa, AngolaNews item - Lucapa
DM1510-2008
2015
Creamers Mining WeeklyUAE chosen as Kimberley Process Chair.Creamers Mining Weekly, Sept. 16, 1/4p.United Arab EmiratesNews item - KP
DM1510-2009
2015
Creamers Mining WeeklyTrans Hex diamond prices down in line with global slump. SomilunaCreamers Mining Weekly, Sept. 16, 1/4p.Africa, South Africa, AngolaNews item - Trans Hex
DM1510-2010
2015
Creamers Mining WeeklySierra Leone economy to shrink one-fifth amid mining crisis.Creamers Mining Weekly, Sept. 16, 1/4p.Africa, Sierra LeoneNews item - economics
DM1510-2011
2015
Creamers Mining WeeklyKimberley Diamonds shares fall as former chairperson arrested ( false information to the market).Creamers Mining Weekly, Sept. 16, 1/4p.AustraliaNews item - Kimberley Diamonds
DM1510-2012
2015
Creamers Mining WeeklyDiamond sales to stabilize in 2015, long term outlook positive.Creamers Mining Weekly, Sept. 22, 1/4p.GlobalNews item - De Beers
DM1510-2013
2015
Creamers Mining WeeklyDiamond prices down on market weakness - Rockwell.Creamers Mining Weekly, Sept. 22, 1/4p.Africa, South AfricaNews item - Rockwell
DM1510-2014
2015
Creamers Mining WeeklyLucapa strikes it lucky in Angola… ten special diamonds. LuloCreamers Mining Weekly, Sept. 22, 1/4p.Africa, AngolaNews item - Lucapa
DM1510-2015
2015
Creamers Mining WeeklyGemfields delivers maiden mineral resource, ore reserve estimates for Kagem. ( emerald)Creamers Mining Weekly, Sept. 23, 1p.Africa, ZambiaNews item - Gemfields
DM1511-2113
2015
Creamers Mining WeeklyLucapa recovers more special diamonds at Angola project. Lulo 90,56,36, 29Creamers Mining Weekly, Sept. 28, 1/4p.Africa, AngolaNews item - Lucapa
DM1511-2114
2015
Creamers Mining WeeklyStornoway lifts Renard resources, sees ample exploration upside.Creamers Mining Weekly, Sept. 28, 1/4p.Canada, QuebecNews item - Stornoway
DM1511-2115
2015
Creamers Mining WeeklyThe destruction of 95 % of South Africa's once bouyant diamond cutting and polishing industry showed once again that governments could not micromanage businesses. Creamers Mining Weekly, Oct. 1, 1p.Africa, South AfricaNews item - cutting and polishing
DM1511-2116
2015
Creamers Mining WeeklyParagon secures $ 15 million for Mothae, Lemphane development.Creamers Mining Weekly, Oct. 2, 1p.Africa, LesothoNews item - Paragon
DM1511-2117
2015
Creamers Mining WeeklyLucapa shares surge on kimberlite confirmation. ( Lulo area)Creamers Mining Weekly, Oct. 6, 1/4p.Africa, AngolaNews item - Lucapa
DM1511-2118
2015
Creamers Mining WeeklyBotswana plans "bold" economic stimulus after diamond price drop.Creamers Mining Weekly, Oct. 12, 1/4p.Africa, BotswanaNews item - economics
DM1511-2119
2015
Creamers Mining WeeklyLucapa sells more Lulo diamonds.Creamers Mining Weekly, Oct. 13, 1/4p.Africa, AngolaNews item - Lucapa
DM1511-2120
2015
Creamers Mining WeeklyLucapa ups alluvial output. LuloCreamers Mining Weekly, Oct. 14, 1/4p.Africa, AngolaNews item - Lucapa
DM1511-2121
2015
Creamers Mining WeeklyDebt-heavy Rockwell juggles operating costs, repayment obligations in Q2 16th. October 2015.Creamers Mining Weekly, Oct. 16, 1/4p.Africa, South AfricaNews item - Rockwell
DM1511-2122
2015
Creamers Mining WeeklyNow Oppenheimer properties edge out of De Beers' diamond route.Creamers Mining Weekly, Oct. 20, 2p.Africa, South AfricaNews item - Oppenheimer
DM1512-2216
2015
Creamers Mining WeeklyWork together or perish together. State diamond trader commentary at Diamond Indaba 2015.Creamers Mining Weekly, Oct. 27, 1p.Africa, South AfricaNews item - beneficiation
DM1512-2217
2015
Creamers Mining WeeklyConsider benefits of cross border diamond beneficiation.Creamers Mining Weekly, Oct. 28, 1/4p.Africa, South Africa, Botswana, NamibiaNews item - economics
DM1512-2218
2015
Creamers Mining WeeklyLucapa sells seventh parcel of Lulo diamonds.Creamers Mining Weekly, Nov. 16, 1/4p.Africa, AngolaNews item - Lucapa
DM1512-2219
2015
Creamers Mining WeeklyGlobal industry comments by Zimnisky ….Creamers Mining Weekly, Nov. 23, 3p.Canada, globalNews item - producers
DM1512-2220
2015
Creamers Mining WeeklyCanadian diamond producers best positioned to weather price crunch.Creamers Mining Weekly, Nov. 24, 1/4p.CanadaNews item - producers
DC1512-2422
2015
Crystal Exploration Inc.Crystal closes diamond projects acquisition. Muskox, Rush and James River properties.Crystal Exploration Inc., Nov. 25, 1p.Canada, Northwest TerritoriesNews item - press release
DS1508-0348
2015
Cucciniello, C., Tucker, R.D., Jourdan, F., Melluso, L., Morra, V.The age and petrogenesis of alkaline magmatism in the Ampasindava Peninsula and Nosy Be archipelago, northern Madagascar.Mineralogy and Petrology, in press available 23p.Africa, MadagascarBasanites, Foidites

Abstract: The Ampasindava alkaline province consists of a series of circular and elliptical intrusions, lava flows, dyke swarms and plugs of Cenozoic age emplaced into the Mesozoic-Cenozoic sedimentary rocks of the Antsiranana basin (NW Madagascar) and above the crystalline basement. The magmatism in the Ampasindava region is linked to a NW-SE trending extensional tectonic setting. New 40Ar/39Ar age determinations on feldspar separate of alkali granites and basaltic dykes yielded ages of 18.01?±?0.36 Ma and 26?±?7 Ma, respectively. Alkali basalts and basanites, nepheline syenites and phonolites, and silica saturated-to-oversaturated syenites, trachytes, granites and rhyolites are the main outcropping lithologies. These rocks have sodic affinity. The felsic rocks are dominant, and range from peraluminous to peralkaline. The mantle-normalized incompatible element patterns of the mafic lavas match those of Na-alkaline lavas in within-plate rift settings. The patterns are identical in shape and absolute concentrations to those of the Bobaomby (Cap d’Ambre) and Massif d’Ambre primitive volcanic rocks. These geochemical features are broadly compatible with variable degrees of partial melting of incompatible element-enriched mantle sources. The mineralogical and geochemical variations are consistent with fractional crystallization processes involving removal of olivine, feldspar, clinopyroxene, amphibole, Fe-Ti oxides and apatite. Removal of small amount of titanite explains the concave upward lanthanide pattern in the evolved nepheline syenites and phonolites, which are additionally rich in exotic silicates typical of agpaitic magmas (eudialyte, F-disilicates).
DS1506-0261
2015
Dannberg, J., Sobolev, S.V.Low-bouyancy thermochemical plumes resolve controversy of classical mantle plume concept.Nature Communications, Vol. 6, 6960 DOI: 10.1038 /ncomms7960MantleMagmatism
DS1512-1907
2015
D'Arpizio, C., Levato, F., Zito, D., De Montgolfier, J.Luxury goods worldwide market study Fall-Winter 2014.Bain & Company, Nov. 5, 38p. PdfGlobalDiamond market
DS1505-0232
2015
Das, J.N.Prospect of gemstones of India in 21st century.Geological Society of America Annual Meeting, Oct. 24, 1p. AbstractIndiaGemstones
DS1510-1764
2015
Das, R., Saikia, U., Rai, S.S.The deep geology of South India inferred from Moho depth and Vp/Vs ratio.Geophysical Journal International, Vol. 203, pp. 910-926.IndiaGeophysics - seismics

Abstract: We present a comprehensive study of thickness and composition of the crust; and the nature of crust-mantle boundary beneath Southern India using P-wave receiver function from 119 seismic stations. Data from distributed network of seismograph location encompass geological domains like mid to late Archean Dharwar craton, Archean and Proterozoic metamorphic terrains, Proterozoic basin, rifted margins and escarpments, and Deccan volcanics. Except for the mid to lower crust exhumed Archean terrains (of West Dharwar and Southern Granulite) all other geological domains have crustal thickness in the range 33-40 km. In the western Dharwar, crustal thickness increases from ~40 km in the north to over 50 km in the south. The Archean domain of granulite terrain is thicker (40-45 km) and more mafic compared to its counterpart in south deformed at 550 Ma. Most of the crustal blocks have low to moderate Vp/Vs (1.72-1.76) representing a felsic to intermediate composition. Exception to the above include Archean granulite terrain with high Vp/Vs (1.76–1.81) suggestive of more mafic crust beneath them. When accounted for the paleo burial depth of 15-25 km, the study suggests a possible Himalaya-Tibet like scenario beneath the mid-late Archean in southwestern Dharwar and north granulite terrain whose deeper crust has progressively densified. This led to a gradational crust-mantle transition that is otherwise sharp elsewhere. The study suggests a more homogenized and felsic nature of the Precambrian crust beneath the terrains formed after 2.6 Ga, possibly due to delamination of the mafic lower crust. Our study does not suggest any distinction between late Archean and Proterozoic crust. The Deccan volcanism at 65 Ma does not appear to have altered the crustal character beneath it and is similar to the adjoining late Archean east Dharwar craton. The western Ghat escarpment and the coastal plain formed due to separation of India from Madagascar are underlain by mafic lower crust.
DS1503-0140
2015
Dauteuil, O., Bessin, P., Guillocheau, F.Topographic growth around the Orange River valley, southern Africa: a Cenozoic record of crustal deformation and climatic change.Geomorphology, Vol. 233, March 15, pp. 5-19.Africa, South AfricaOrange River

Abstract: We reconstruct the history of topographic growth in southern Africa on both sides of the Orange River valley from an integrated analysis of erosion surfaces, crustal deformation and climate change. First, we propose an inventory of erosion surfaces observed in the study area and classify them according to their most likely formative process, i.e. chemical weathering or mechanical erosion. Among the various land units observed we define a new class of landform: the pedivalley, which corresponds to a wide valley with a flat erosional floor. In the Orange River valley, we mapped three low-relief erosion surfaces, each bevelling a variety of lithologies. The oldest and most elevated is (1) a stripped etchplain evolving laterally into (2) a stepped pediplain bearing residual inselbergs; (3) a younger pediplain later formed in response to a more recent event of crustal deformation. These are all Cenozoic landforms: the etchplain is associated with a late Palaeocene to middle Eocene weathering event, and the two pediplains are older than the middle Miocene alluvial terraces of the Orange River. Landscape evolution was first driven by slow uplift (10 m/Ma), followed by a second interval of uplift involving a cumulative magnitude of at least 200 m. This event shaped the transition between the two pediplains and modified the drainage pattern. A final phase of uplift (magnitude: 60 m) occurred after the Middle Miocene and drove the incision of the lower terraces of the Orange River. Climate exerted a major control over the denudation process, and involved very humid conditions responsible for lateritic weathering, followed by more arid conditions, which promoted the formation of pedivalleys. Collectively, these produce pediplains.
DS1509-0392
2015
Davies, C., Pozzo, M., Gubbins, D., Alfe, D.Constraints from material properties on the dynamics and evolution of Earth's core.Nature Geoscience, Vol. 8, pp. 678-785.MantleHT - core evolution

Abstract: The Earth’s magnetic field is powered by energy supplied by the slow cooling and freezing of the liquid iron core. Efforts to determine the thermal and chemical history of the core have been hindered by poor knowledge of the properties of liquid iron alloys at the extreme pressures and temperatures that exist in the core. This obstacle is now being overcome by high-pressure experiments and advanced mineral physics computations. Using these approaches, updated transport properties for FeSiO mixtures have been determined at core conditions, including electrical and thermal conductivities that are higher than previous estimates by a factor of two to three. Models of core evolution with these high conductivities suggest that the core is cooling much faster than previously thought. This implies that the solid inner core formed relatively recently (around half a billion years ago), and that early core temperatures were high enough to cause partial melting of the lowermost mantle. Estimates of core-mantle boundary heat flow suggest that the uppermost core is thermally stratified at the present day.
DS1512-1908
2015
Davies, D.R., Rawlinson, N., Iaffaldano, G., Campbell, I.H.Lithospheric controls on magma composition along Earth's longest continental hotspot track.Nature, Vol. 525, 7570, pp. 511-514.AustraliaCosgrove track

Abstract: Hotspots are anomalous regions of volcanism at Earth’s surface that show no obvious association with tectonic plate boundaries. Classic examples include the Hawaiian-Emperor chain and the Yellowstone-Snake River Plain province. The majority are believed to form as Earth’s tectonic plates move over long-lived mantle plumes: buoyant upwellings that bring hot material from Earth’s deep mantle to its surface1. It has long been recognized that lithospheric thickness limits the rise height of plumes2, 3, 4 and, thereby, their minimum melting pressure. It should, therefore, have a controlling influence on the geochemistry of plume-related magmas, although unambiguous evidence of this has, so far, been lacking. Here we integrate observational constraints from surface geology, geochronology, plate-motion reconstructions, geochemistry and seismology to ascertain plume melting depths beneath Earth’s longest continental hotspot track, a 2,000-kilometre-long track in eastern Australia that displays a record of volcanic activity between 33 and 9 million years ago5, 6, which we call the Cosgrove track. Our analyses highlight a strong correlation between lithospheric thickness and magma composition along this track, with: (1) standard basaltic compositions in regions where lithospheric thickness is less than 110 kilometres; (2) volcanic gaps in regions where lithospheric thickness exceeds 150 kilometres; and (3) low-volume, leucitite-bearing volcanism in regions of intermediate lithospheric thickness. Trace-element concentrations from samples along this track support the notion that these compositional variations result from different degrees of partial melting, which is controlled by the thickness of overlying lithosphere. Our results place the first observational constraints on the sub-continental melting depth of mantle plumes and provide direct evidence that lithospheric thickness has a dominant influence on the volume and chemical composition of plume-derived magmas.
DS1502-0052
2015
Day, J.M.D.Planet formation processes revealed by meteorites.Geology Today, Vol. 31, 1, pp. 12-20.TechnologyMeteorite
DC1501-1433
2014
De Beers Canada Inc.Gahcho Kue joint venture and NWT Metis Nation sign impact benefit agreement.De Beers Canada , Dec. 15, 2p.Canada, Northwest TerritoriesNews item - press release
DC1511-2374
2015
De Beers Canada Inc.De Beers Canada to move headquarters to Calgary from Toronto ( by June 2016)De Beers Canada, Oct. 16, 1/2p.CanadaNews item - De Beers
DC1502-1434
2014
De Beers GroupGahcho Kue joint venture and Deninu Kue First Nation sign impact benefit agreement.De Beers Group, Dec. 24, 1p.Canada, Northwest TerritoriesNews item - press release
DC1502-1435
2015
De Beers GroupDe Beers Group CEO steps out to support Forevermark "high impact" brand strategy.De Beers Group, Jan. 8, 1p.GlobalNews item - press release
DC1502-1436
2015
De Beers GroupDe Beers announces 2015 auction sales programme for forward contract sales.De Beers Group, Jan. 21, 1p.GlobalNews item - press release
DC1503-1440
2015
De Beers GroupInternational institute of diamond grading & research set for Indian roadshow.De Beers Group of Companies, Feb. 16, 1p.IndiaNews item - press release
DC1505-1441
2015
De Beers GroupPaul Rowley: we must all invest now to increase our future returns. VP of Global Sightholder Sales speaking at Dubai Diamond Conference.De Beers Group of Companies, Apr. 21, 1p. GlobalNews item - De Beers
DC1506-1437
2015
De Beers GroupDe Beers seeks expression of interest for Kimberley Mines tailings Operation.De Beers Group, May 21, 1p.Africa, South AfricaNews item - press release
DC1507-1438
2015
De Beers GroupReport to Society.. Building Forever 2014De Beers Group, June 5, GlobalNews item - press release
DC1507-1439
2015
De Beers GroupPhillippe Mellier: Sustainable returns across the diamond pipeline are key to investment.De Beers Group, June 16, 3p.GlobalNews item - De Beers
DC1508-1432
2015
De Beers GroupNamibia and De Beers reach agreement on Milestone 10 year diamond sales agreement.De Beers, July 21, 1p.Africa, NamibiaNews item - NDTC
DC1510-2338
2015
De Beers Group104 carat Forevermark diamond unveiled by long standing Forevermark Diamantaire … De Beers Group, Sept. 7, 1p.Hong KongNews item - Cullinan Heritage
DC1510-2339
2015
De Beers GroupInternational Institute of diamond grading & research to launch synthetic melee screening and referrals testing service in India.De Beers Group, Sept. 14, 1p.IndiaNews item - press release
DC1510-2340
2015
De Beers GroupDiamond industry fundamentals support long-term confidence in sector as India presents further growth opportunity.De Beers Group, Sept. 21, 1p.IndiaNews item - press release
DC1510-2341
2015
De Beers GroupDe Beers insight report 2015 - global consumer demand, rough diamond pipeline, in focus: the Indian consumer.De Beers Group, 44p.Global, IndiaNews item - demand, piepline, consumer
DC1511-2375
2015
De Beers GroupInternational Institute of diamond grading & research launches melee testing service. HDGR low cost-high volume.De Beers Group of Companies, Oct. 21, 1p.India, Europe, BelgiumNews item - De Beers
DC1512-2423
2015
De Beers GroupDe Beers to launch social campaign to honour inspirational women globally.news360.com, Nov. 10, 1/2p.GlobalNews item - De Beers
DC1512-2424
2015
De Beers GroupConnecting resources and society conference to be held in Botswana.De Beers Group of Companies, Nov. 13, 1p.Africa, BotswanaNews item - press release
DC1510-2342
2015
De Grey Mining Ltd.De Grey opts out of agreement to acquire interest in diamond project. IIIP Prospect PR 856 in Kimberley district.De Grey Mining Ltd., Sept. 8, 1p.Africa, South AfricaNews item - press release
DS1512-1909
2015
De Lamotte, F., Fourdan, D., Leleu, B., Leparmentier, S., Clarens, F.Style of rifting and the stages of Pangea.Tectonics, Vol. 34, 5, pp. 1009-1029.MantlePangea

Abstract: Pangea results from the progressive amalgamation of continental blocks achieved at 320?Ma. Assuming that the ancient concept of “active” versus “passive” rifting remains pertinent as end-members of more complex processes, we show that the progressive Pangea breakup occurred through a succession of rifting episodes characterized by different tectonic evolutions. A first episode of passive continental rifting during the Upper Carboniferous and Permian led to the formation of the Neo-Tethys Ocean. Then at the beginning of Triassic times, two short episodes of active rifting associated to the Siberian and Emeishan large igneous provinces (LIPs) failed. The true disintegration of Pangea resulted from (1) a Triassic passive rifting leading to the emplacement of the central Atlantic magmatic province (200?Ma) LIP and the subsequent opening of the central Atlantic Ocean during the lowermost Jurassic and from (2) a Lower Jurassic active rifting triggered by the Karoo-Ferrar LIP (183?Ma), which led to the opening of the West Indian Ocean. The same sequence of passive then active rifting is observed during the Lower Cretaceous with, in between, the Parana-Etendeka LIP at 135?Ma. We show that the relationships between the style of rifts and their breakdown or with the type of resulting margins (as magma poor or magma dominated) are not straightforward. Finally, we discuss the respective role of mantle global warming promoted by continental agglomeration and mantle plumes in the weakening of the continental lithosphere and their roles as rifting triggers.
DS1503-0141
2015
De Wit, M.C.J., Jelsma, H.A.A review of the kimberlites of the Democratic Republic of Congo.Geology and resource potential of the Congo Basin, Springer Regional Geology Reviews, Chapter 17, 9p.Africa, Democratic Republic of CongoOverview, history

Abstract: An overview is provided of the exploration history and geological setting of the kimberlites in the Democratic Republic of Congo (DRC). Exploration for diamonds, in what was then known as Congo Belge, started in 1900 and the first diamonds were found in 1903 in Shaba (now Katanga) Province, in 1907 in Kasai Occidental Province near Tshikapa Town and in 1918 in Kasai Oriental Province near Mbuji Mayi Town. While the Kundelungu kimberlites in Katanga Province were discovered in 1908, other kimberlite fields were discovered much later (Mbuji Mayi 1946; Tshibwe 1956; Bas-Congo 1974; Kasendou and Lukashi 2005), during exploration work by Forminière (Société Internationale Forestière et Minière du Congo-Tshikapa), MIBA (Societé Minière de Bakwanga-Mbuji Mayi), the De Beers Group and Bugeco S.A. Published age constraints on the kimberlites show Late Cretaceous ages for the Mbuji Mayi kimberlites (~70 Ma) and Eocene-Oligocene ages for the Kundelungu kimberlites (~32 Ma). Emplacement of the Late Cretaceous kimberlites (Mbuji Mayi, Tshibwe, Kasendou and Lukashi) was concomitant with the deposition of Cretaceous sedimentary sequences. The majority of the pipes show crater-facies preservation and some of the pipes are flared displaying so-called ‘champagne glass-shaped’ morphologies, suggesting emplacement into unconsolidated sediments overlying basement. The age of the Eocene-Oligocene Kundelungu kimberlites corresponds to lithospheric extension associated with the southward propagation of the East African Rift.
DS1503-0142
2015
De Wit, M.C.J., Thorose, E.Diamond bearing gravels along the lower Kwango River, DRC.Geology and resource potential of the Congo Basin, Springer Regional Geology Reviews, Chapter 16, 20p.Africa, Democratic Republic of CongoOverview, history

Abstract: Since the mid-1950s the Kwango River has been a major target for alluvial diamonds which are and continue to be mined from its terraces, younger river flats and present-day river channel. The terraces have maximum ages of Early to Middle Pleistocene. Most of the diamonds have been recovered from large diamond placers in and along the Angolan section of this river—the Cuango River. Smaller deposits have been worked further downstream, where the Kwango River forms the international border between Angola and the Democratic Republic of Congo (DRC), also referred to as the ‘international’ Kwango. The prospecting history of this river goes back to 1906 but a systematic exploration program over the lower Kwango was only initiated in 2005. The application of geophysics to explore the terrace deposits and river flats has been very useful, but a programme of drilling and pitting was required to accurately define gravel and overburden thicknesses, and outline palaeo-channels. A diamond study used to glean information on diamond sizes and characteristics added significant value to the understanding of these alluvial deposits. For most of the international Kwango, terraces and river flats overly aeolian facies of Upper Kwango Group. Basement rocks, providing more favourable sites for diamond concentrations, are only exposed over a relatively short section, just upstream from Tembo. The basal part of the Cretaceous Kwango Group is locally composed of chemically mature gravels with diamonds in economic quantities only proximal to primary sources and no such settings were found in the project area. The size frequency of the diamonds from the international Kwango indicates that these form the distal head of the diamond trail that have been eroded out of the Cretaceous Kwango Group sediments and kimberlites in the Upper Cuango basin in Angola since the Pleistocene. The diamonds below the two major waterfalls along the international Kwango near Tembo, the Guiliame and Francois-Joseph Falls, show a high percentage of breakage and a decline in average diamond size from around 0.25 cts/stn above the falls to between 0.07 and 0.1 cts/stn in the Nzasi Muadi to Kitangu area between 20 km and 130 km below the Falls. However, local variations due to geomorphological influences affect diamond concentrations and sizes. A preliminary assessment of the terrace deposits suggests that these are uneconomic at present using modern mining methods. This is largely due to thick overburden (up to 12 m of sand) combined with thin and hence low-volume, medium-grade basal gravel, and the dominance of small diamonds of lower value.
DS1509-0393
2015
De Wit, R.W.L., Trampert, J.Robust constraints on average radial lower mantle anisotropy and consequences for composition and texture.Earth and Planetary Science Letters, Vol. 429, pp. 101-109.MantleSeismic -anisotropy

Abstract: The seismic structure of Earth’s inner core is highly complex, displaying strong anisotropy and further regional variations. However, few seismic waves are sensitive to the inner core and fundamental questions regarding the origin of the observed seismic features remain unanswered. Thus, newtechniques to observe different types of inner corewaves are imperative to improve data coverage. Here, we detail our method for detecting exotic inner core phases such as PKJKP and PKIIKP, using inner core compressional waves as proof of concept.We use phase weighted stacking on long period data from a global distribution of stations, and employ several synthetic methods, including normal mode summation and SPECFEM, to identify and confirm the inner core phases. We present evidence for two observations of exotic inner core compressional waves, and apply the technique to a previously detected inner core shear wave. A possible new inner core shear wave remains unconfirmed. Additionally, we show how our method is important for rejecting potential observations, and distinguishing between waves with similar traveltime and slowness. The method is most successful for detecting exotic inner core compressional waves, and will provide a new approach for studying the compressional wave structures in the upper inner core.
DC1502-1442
2015
Debut Diamonds Inc.Debut Diamonds Inc. completes private placement. $ 50,000. ( Macfadyen and Good Friday pipes)Debut Diamonds Inc., Jna. 8, 1p.Canada, Ontario, AttawapiskatNews item - press release
DC1503-1443
2015
Debut Diamonds Inc.Debut Diamonds Inc. completes private placement. McFadyen Debut Diamonds Inc., Jan. 27, 1p.Canada, OntarioNews item - press release
DS1511-1830
2015
Decree, S., Boulvais, P., Tack, L., Andre, L., Baele, J-M.Fluorapatite in carbonatite-related phosphate deposits: the case of the Matongo carbonatite. ( Burundi)Mineralium Deposita, in press available 14p.Africa, BurundiCarbonatite

Abstract: The Matongo carbonatite intrusive body in the Neoproterozoic Upper Ruvubu alkaline plutonic complex (URAPC) in Burundi is overlain by an economic phosphate ore deposit that is present as breccia lenses. The ore exhibits evidence of supergene enrichment but also preserves textures related to the concentration of fluorapatite in the carbonatitic system. Magmatic fluorapatite is abundant in the ore and commonly occurs as millimeter-sized aggregates. It is enriched in light rare earth elements (LREE), which is especially apparent in the final generation of magmatic fluorapatite (up to 1.32 wt% LREE2O3). After an episode of metasomatism (fenitization), which led to the formation of K-feldspar and albite, the fluorapatite-rich rocks were partly brecciated. Oxygen and carbon isotope compositions obtained on the calcite forming the breccia matrix (d18O?=?22.1?- and d13C?=?-1.5?‰) are consistent with the involvement of a fluid resulting from the mixing of magmatic-derived fluids with a metamorphic fluid originating from the country rocks. In a subsequent postmagmatic event, the carbonates hosting fluorapatite were dissolved, leading to intense brecciation of the fluorapatite-rich rocks. Secondary carbonate-fluorapatite (less enriched in LREE with 0.07-0.24 wt% LREE2O3 but locally associated with monazite) and coeval siderite constitute the matrix of these breccias. Siderite has d18O values between 25.4 and 27.7?- and very low d13C values (from -12.4 to -9.2?, which are consistent with the contribution of organic-derived low d13C carbon from groundwater. These signatures emphasize supergene alteration. Finally, the remaining voids were filled with a LREE-poor fibrous fluorapatite (0.01 wt% LREE2O3), forming hardened phosphorite, still under supergene conditions. Pyrochlore and vanadiferous magnetite are other minerals accumulated in the eluvial horizons. As a consequence of the supergene processes and fluorapatite accumulation, the phosphate ore, which contains 0.72 to 38.01 wt% P2O5, is also enriched in LREE (LaN/YbN from 47.1 to 83.5; SREE between 165 and 5486 ppm), Nb (up to 656 ppm), and V (up to 1232 ppm). In the case of phosphate exploitation at Matongo, REE could prove to have a subeconomic potential to be exploited as by-products of phosphates.
DS1511-1831
2015
Deljanin, B., Alessandri, M., Peretti, A., Astrom, M.NDT breaking the 10 carat barrier: world record faceted and gem-quality synthetic diamonds.Contributions to Gemology, Vol. 15, pp. 1-7.TechnologySynthetics

Abstract: The first small manufactured industrial diamonds were produced in 1953 by the Swedish company ASEA but their accomplishment went unannounced. In 1970, General Electric (GE) produced synthetic diamond crystals using the HPHT method with a belt type of press and created a 0.78ct polished RBC colorless diamond. In the 1980’s and 1990’s Russians used their own technology (“BARS” and “TOROID” high pressure apparatus (HPA) with high pressure presses of up to 25 MN load) to grow industrial and crystals up to 2.00ct in polished size, mostly orange to yellow in colour. In the last 15 years, companies including Lucent, Chatham, AOTC, Gemesis (now IIa Technologies) and many other producers in China, Germany, India, Russia, Ukraine, USA and Taiwan have improved the technology yet again and used their expertise to successfully grow diamond crystals that cut to 1.00ct up to 2.00ct in size. This “next generation” of diamonds exhibited high clarities (VS and VVS) and colours (D-H), as well as new blue and pink colours (after irradiation). Other companies (ref. 2-3) including Scio Diamonds, Washington Diamonds, Taidiam, PDC diamonds and Pure Grown Diamonds (selling arm of IIa technologies) are also using a very different technology/process of Chemical Vapour Deposition (CVD) to produce laboratory-grown diamonds up to 3.00 ct in size (table 1).
DS1504-0192
2014
Delpit, S., Ross, P-S., Hearn, B.C.Deep bedded ultramafic diatremes in the Missouri River Breaks volcanic field, Montana, USA.Bulletin of Volcanology, Vol. 76, p. 832-United States, MontanaDiatreme
DS1506-0263
2015
DeStefano, A., Shiroki, A., Zhuk, V., Gaudet, M.Detailed studies of Renard 2 kimberlite - some practical aspects.Vancouver Kimberlite Cluster, May 27, 1/4p. AbstractCanada, QuebecDeposit - Renard
DM1511-2123
2015
Devenish, C.Charles is a strong environmentalist in India and asks that mining and agriculture support each other. Articles by Colin Todhunter ColinTodHunter.com, charlesdevenish @geomysore.comIndiaNews item - CSR
DS1502-0053
2010
deVera, J., Granado, P., McClay, K.Structural evolution of the Orange Basin gravity-driven system, offshore Namibia.Marine and Petroleum Geology, Vol. 27, 1, pp. 223-237.Africa, NamibiaStructure
DS1501-0006
2014
Devriese, S.G.R., Corcoran, N., Cowan, D., Davis, K., Bild-Enkin, D., Fournier, D., Heagy, L., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Magnetic inversion of three airborne data sets over the Tli Kwi Cho kimberlite complex.SEG Annual Meeting Denver, 5p. Extended abstractCanada, Northwest TerritoriesDeposit - Tli Kwi Cho, geophysics

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three papers. In the first, we find a 3D magnetic susceptibility model for the area; in the second, we find a 3D conductivity model; and in the third paper, we find a 3D chargeability model. Our goal is to explain all the geophysical results within a geologic framework. In this first paper, we invert three independent airborne magnetic data sets flown over the Tli Kwi Cho kimberlite complex located in the Lac de Gras kimberlite field in Northwest Territories, Canada. The complex consists of two kimberlites known as DO-27 and DO-18. An initial airborne DIGHEM survey was flown in 1992 and AeroTEM and VTEM data subsequently acquired in 2003 and 2004, respectively. In this paper, we invert each magnetic data set in three dimensions. Both kimberlites are recovered in each model, with DO-27 as a more susceptible body than DO-18. Our goal is to simultaneously invert the three data sets to generate a single susceptibility model for Tli Kwi Cho. This project is part of a larger, on-going investigation by UBC-GIF on inverting magnetic, electromagnetic, and induced polarization data from the Tli Kwi Cho area.
DS1503-0143
2015
Dey, S., Nandy, J., Choudhary, A.K., Liu, Y., Zong, K.Neoarchean crustal growth by combined arc-plume action: evidence from the Kadiri greenstone belt, eastern Dharwar craton, India.Geological Society of London Special Publication: Continent formation through time., No. 389, pp. 135-163.IndiaGeotectonics

Abstract: Field and geochemical studies combined with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) zircon U-Pb dating set important constraints on the timing and petrogenesis of volcanic rocks of the Neoarchaean Kadiri greenstone belt and the mechanism of crust formation in the eastern Dharwar craton (EDC). The volcanic rocks are divided into three suites: tholeiitic basalts, calc-alkaline high-Mg# andesites and dominant dacites-rhyolites. The basalts (pillowed in places) show flat rare earth element (REE) and primordial mantle-normalized trace element patterns, but have minor negative Nb and Ta anomalies. They are interpreted as mantle plume-related oceanic plateau basalts whose source contained minor continental crustal input. The andesites are characterized by high Mg# (0.66-0.52), Cr and Ni, with depletion of high-field strength elements (HFSE) and enrichment of light REE (LREE) and large-ion lithophile elements (LILE). They were probably derived from a metasomatized mantle wedge overlying a subducted slab in a continental margin subduction zone. The dacites-rhyolites are silicic rocks (SiO2 = 61-72 wt%) with low Cr and Ni, K2O/Na2O mostly 0.5-1.1, highly fractionated REE patterns, enrichments of LILE and distinctly negative HFSE anomalies. One rhyolite sample yielded a zircon U-Pb age of 2353 ± 32 Ma. This suite is similar to potassic adakites and is explained as the product of deep melting of thickened crust in the arc with a significant older crustal component. Collision between a continental margin arc with an oceanic plateau followed by slab break-off, upwelling of hot asthenosphere and extensive crustal reworking in a sustained compressional regime is proposed for the geodynamic evolution of the area. This is in corroboration with the scenario of EDC as a Neoarchaean hot orogen as suggested recently by some workers.
DS1512-1910
2015
D'Haenens-Johansson, U.F.S., Katrusha, A., Moe, K.S., Johnson, P., Wang, W.Large colorless HPHT synthetic diamonds from new diamond technology. Using spectroscopic and gemological analysis.Gems & Gemology, Vol. 51, 3, pp. 260-79.TechnologySynthetics

Abstract: The Russian company New Diamond Technology is producing colorless and near-colorless HPHT-grown synthetic diamonds for the gem trade. Forty-four faceted samples synthesized using modified cubic presses were analyzed using a combination of spectroscopic and gemological techniques to characterize the quality of the material and determine the means of distinguishing them from natural, treated, and alternative laboratory-grown diamonds. These samples, with weights ranging from 0.20 to 5.11 ct, had color grades from D to K and clarity grades from IF to I2. Importantly, 89% were classified as colorless (D-F), demonstrating that HPHT growth methods can be used to routinely achieve these color grades. Infrared absorption analysis showed that all were either type IIa or weak type IIb, and photoluminescence spectroscopy revealed that they contained Ni-, Si-, or N-related defects. Their fluorescence and phosphorescence behavior was investigated using ultraviolet excitation from a long-wave/short-wave UV lamp, a DiamondView instrument, and a phosphorescence spectrometer. Key features that reveal the samples’ HPHT synthetic origin are described.
DS1508-0349
2015
Dhuime, B., Wuestefeld, A., Hawkesworth, C.J.Emergence of modern continental crust about 3 billion years ago.Nature Geoscience, Vol. 8, pp. 552-555.MantleGeochronology Rb/Sr
DC1507-1444
2015
Diamante Minerals, Inc.Diamante provides update on Mineracao Batovi diamond project.Diamante Minerals, Inc., June 5, 2p.South America, Brazil, Mato GrossoNews item - press release
DC1508-1445
2015
Diamante Minerals, Inc.Announces new chief financial officer. BatoviDiamante Minerals, Inc., July 9, 1p.South America, Brazil, Mato GrossoNews item - press release
DC1501-1446
2014
Diamcor Mining Inc.MD&A ended Sept. 30, 2014 - Corporate highlights Krone-Endora.Diamcor Mining Inc., Dec. 1, 1p.Africa, South AfricaNews item - press release
DC1501-1447
2014
Diamcor Mining Inc.Diamcor achieves significant milestone in second fiscal quarter. A full mining right from the South African Dept. of Minerals and resources in respect of Krone-Endora.Diamcor Mining Inc., Dec. 4, 2p.Africa, South AfricaNews item - press release
DC1502-1448
2014
Diamcor Mining Inc.Diamcor closes private placement of CDB $ 3,133,600 Diamcor Mining Inc., Dec. 31, 1p.Africa, South AfricaNews item - press release
DC1503-1449
2015
Diamcor Mining Inc.Diamcor commences expansion/ targets implementation. Krone-EndoraDiamcor Mining Inc., Feb. 5, 1p.Africa, South AfricaNews item - press release
DC1504-1450
2015
Diamcor Mining Inc.Diamcor third quarter fiscal 2015 results. Krone-EndoraDiamcor Mining Inc., Feb. 26, 2p.Africa, South AfricaNews item - press release
DC1505-1451
2015
Diamcor Mining Inc.Fourth quarter diamond sales and upgrade progress at Krone-Endor at Venetia.Diamcor Mining Inc., Apr. 15, 4p.Africa, South AfricaNews item - press release
DC1506-1452
2015
Diamcor Mining Inc.Diamcor files updated technical report for Krone-Endora at Venetia project.Diamcor Mining Inc., Apr. 28, 2p.Africa, South AfricaNews item - press release
DC1508-1453
2015
Diamcor Mining Inc.Diamcor first quarter diamond sales and operational update at Krone-Endora at Venetia.Diamcor Mining Inc., July 20, 2p.Africa, South AfricaNews item - press release
DC1511-2376
2015
Diamcor Mining Inc.Diamcor second fiscal quarter sales and operational update at Krone-Endora at Venetia.Diamcor Mining Inc., Oct. 6, 3p.Africa, South AfricaNews item - press release
DC1512-2425
2015
Diamcor Mining Inc.Diamcor preparing for largest rough diamond tender to date. Krone-EndoraDiamcor Mining Inc., Oct. 30, 1p.Africa, South AfricaNews item - press release
DC1507-1454
2015
Diamond Fields International Ltd.Diamond Fields International restarts Namibian diamond operations.Diamond Fields International Ltd., June 5, 1p.Africa, NamibiaNews item - press release
DC1512-2426
2015
Diamond Fields International Ltd.Diamond Fields is pleased to announce that offshore marine sampling operations have begun ML-111Diamond Fields International Ltd., Nov. 16, 1p.Africa, NamibiaNews item - press release
DM1512-2326
2015
Diamond Intelligence BriefingDe Beers defers its own Debswana rough purchases.Diamond Intellgence Briefing, Nov. 12, 7p.Africa, BotswanaNews item - De Beers
DM1502-0544
2015
Diamond Investing NewsWhat are nanodiamonds ( outline for the layman)Diamond Investing News, Jan. 1, 1p.TechnologyNews item - nanodiamonds
DM1504-0545
2015
Diamond Investing NewsTrans Hex announces an update of latest diamond sales and production.Diamond Investing News, Mar. 5, 1/4p.Africa, South AfricaNews item - Trans Hex
DM1507-0546
2015
Diamond Investing News5 top industrial diamond producing countries ( DRC, Russia, Australia, Botswana, South Africa)diamondinvestingnews.com, June 18, 2p.GlobalNews item - industrial diamonds
DM1508-2466
2015
Diamond Investing newsHigh hopes for Lucara Diamond's first 2015 exceptional stone tender.Diamond Investing News, July 13, 1p.Africa, BotswanaNews item - Lucara
DM1511-2208
2015
Diamond Investing NewsCan miners buck the diamond price trend 2015?Diamond Investing News, Oct. 19, 2p.GlobalNews item - prices
DC1509-1456
2015
DiamondCorp plc.Lace diamond mine project update. Upper K4 unit.DiamondCorp plc., July 31, 4p.Africa, South AfricaNews item - press release
DC1510-2343
2015
DiamondCorp Plc.Interim results…. Lace mine.DiamondCorp Plc., Sept. 1, 4p.Africa, South AfricaNews item - press release
DC1511-2377
2015
DiamondCorp Plc.Conveyor belt installation complete ( 400 tonne per hour) at Lace mine.DiamondCorp. Plc, Oct. 13, 2p.Africa, South AfricaNews item - press release
DC1512-2427
2015
DiamondCorp plc.Lace diamond mine project update … detailed.DiamondCorp plc, Nov. 3, 1p.Africa, South AfricaNews item - press release
DC1512-2428
2015
DiamondCorp plc.Conveyor belt commissioned. Lace mineDiamondCorp plc, Nov. 12, 1p.Africa, South AfricaNews item - press release
DC1512-2429
2015
DiamondCorp plc.Lace mine - 290m level development resumes.DiamondCorp plc, Nov. 20, 1p.Africa, South AfricaNews item - press release
DS1512-1911
2015
Diamonds in CanadaBig changes at De Beers Canada.. New CEO discusses HQ move to Calgary.Diamonds in Canada Magazine, Northern Miner, Nov. pp. 18-19.Canada, AlbertaDe Beers Headquarters
DS1512-1912
2015
Diamonds in CanadaStornoway benefits from 'good timing'. Renard on track for commercial production in 2017.Diamonds in Canada Magazine, Northern Miner, Nov. pp. 20-21.Canada, QuebecDeposit - Renard
DS1512-1913
2015
Diamonds in CanadaSable PEA sweetens Ekati. Dominion works to add mine life to operation.Diamonds in Canada Magazine, Northern Miner, Nov. 22-23.Canada, Northwest TerritoriesDeposit - Sable
DM1501-0547
2014
Diamonds.netAnjin's failed promise turns former Marange nonagenarian destitute.Diamonds.net, Dec. 1, 1/4p.Africa, ZimbabweNews item - Anjin
DM1501-0548
2014
Diamonds.netSierra Leone issues investor statement on Sunergy Inc. License from NWA false. Diamonds.net, Dec. 1, 1/4p.Africa, Sierra LeoneNews item - Sunergy
DM1501-0549
2014
Diamonds.netFirestone on track to commence Liquobong production in 2Q 2016.Diamonds.net, Dec. 2, 1/4p.Africa, LesothoNews item - Firestone
DM1501-0550
2014
Diamonds.netArgyle Champagne diamond raises money for women in mining internship.Diamonds.net, Dec. 4, 1/4p.Global, EnglandNews item - Argyle, Rio Tinto
DM1501-0551
2014
Diamonds.netThe diamond decade so far. Diamonds.net, Dec. 5, 2p.GlobalNews item - history
DM1501-0552
2014
Diamonds.netLiori Diamonds engagement survey shows growing interest in black diamonds.Diamonds.net, Dec. 3, 1p.GlobalNews item - Liori
DM1501-0553
2014
Diamonds.netVenezuela adds diamonds to financial reserves to strengthen security and currency. Withdrew from KP in 2008. No Venezuelan reports to date ( suspected smuggling through Brazil and Guyana).Diamonds.net, Dec. 5, 1/4p.South America, VenezuelaNews item - legal
DM1501-0554
2014
Diamonds.netPresident Putin, Prime Minister Modi to address World Diamond Conference.Diamonds.net, Dec. 7, /4p.IndiaNews item - GJEPC
DM1501-0555
2014
Diamonds.netLace mine workers end strike, resume work on Dec. 8.Diamonds.net, Dec. 7, /4p.Africa, South AfricaNews item - DiamondCorp
DM1501-0556
2014
Diamonds.netStellar Diamonds prepares Baoule rough for sale in Antwerp.Diamonds.net, Dec. 4, 1/4p.Africa, GuineaNews item - Stellar
DM1501-0557
2014
Diamonds.netDiamond explorer ( Delrand) votes on plan to sell Congo Licenses for $1Diamonds.net, Dec. 7, /4p.Africa, Democratic Republic of CongoNews item - Delrand
DM1501-0558
2014
Diamonds.netConsumers starting to embrace lab-grown diamonds.Diamonds.net, Dec. 7, /4p.TechnologyNews item - Diamaz International
DM1501-0559
2014
Diamonds.netAWDC and Bain & Co. release fourth annual diamond industry report. SEE Technical refs for full report ref.Diamonds.net, Dec. 9, 1/4p.GlobalNews item - Bain
DM1501-0560
2014
Diamonds.netBelgium's competition authority dismisses Spira's complaint against De Beers.Diamonds.net, Dec. 8, 1/4p.Europe, BelgiumNews item - De Beers
DM1501-0561
2014
Diamonds.netRio Tinto's Partnership model to drive diamond jewelry growth in India.Diamonds.net, Dec. 11, 1/4p.IndiaNews item - Rio Tinto
DM1501-0562
2014
Diamonds.netLucara sets top revenue target at $ 240 million for 2015.Diamonds.net, Dec. 11, 1/4p.Africa, BotswanaNews item - Lucara
DM1501-0563
2014
Diamonds.netAlrosa takes measures to improve liquidity.Diamonds.net, Dec. 12, 1/4p.RussiaNews item - Alrosa
DM1501-0564
2014
Diamonds.netSightholders reject goods at $600 m December De Beers sight.Diamonds.net, Dec. 16, 1/4p.GlobalNews item - De Beers
DM1501-0565
2014
Diamonds.netCote d'Ivoire resumes diamond trade with Belgian help.Diamonds.net, Dec. 16, 1/4p.Africa, Ivory CoastNews item - KP
DM1501-0566
2014
Diamonds.netGahcho Kue operators sign impact agreement with Metis Nation.Diamonds.net, Dec. 15, 1/4p.Canada, Northwest TerritoriesNews item - De Beers, Mountain Province
DM1501-0567
2014
Diamonds.netNasdaq approves listing for Mountain Province Diamonds.Rough-Polished.com, Dec. 19, 1/4p.Canada, Northwest TerritoriesNews item - Mountain Province
DM1501-0568
2014
Diamonds.netLucapa to start alluvial mining at Lulo in January.Diamonds.net, Dec. 18, 1/4p.Africa, AngolaNews item - Lucapa
DM1502-0569
2014
Diamonds.netDiamond grade improves in the latest Kelvin mini-bulk sample.Diamonds.net, Dec. 24, 1/4p.Canada, Northwest TerritoriesNews item - Kennady
DM1502-0570
2014
Diamonds.netDecree taps Alrosa, Kristall to reduce foreign currency holdings.Diamonds.net, Dec. 24, 1/4p.RussiaNews item - Alrosa, Kristall
DM1502-0571
2014
Diamonds.netPeregrine Diamonds placement to raise $ 2 million.Diamonds.net, Dec. 22, 1/4p.Canada, Nunavut, Baffin IslandNews item - Peregrine
DM1502-0572
2014
Diamonds.netLukoil targets production of 2 million carats in 2015.Diamonds.net, Dec. 29, 1/4p.Russia, Kola Peninsula, ArchangelNews item - Lukoil
DM1502-0573
2014
Diamonds.netSRK signs supply contract with Alrosa. Diamonds.net, Dec. 29, 1/4p.RussiaNews item - SRK, Alrosa
DM1502-0574
2014
Diamonds.netThe diamond story of 2014…. Reduction of bank credit available is a game changer.Diamonds.net, Dec. 26, 4p.GlobalNews item - economics
DM1502-0575
2014
Diamonds.netMbada Diamonds workers picket for unpaid salary.Diamonds.net, Dec. 24, 1/4p.Africa, ZimbabweNews item - Mbada
DM1502-0576
2014
Diamonds.netRussia orders Alrosa, Kristall to sell foreign currency.Diamonds.net, Dec. 23, 1/4p.RussiaNews item - Alrosa, Kristall
DM1502-0577
2014
Diamonds.netSarine delivers its first Galaxy ultra microscopic inclusion mapping service.Diamonds.net, Dec. 30, 1/4p.TechnologyNews item - Sarine
DM1502-0578
2015
Diamonds.netStellar Diamonds postpones first Baoule diamond sale to late January.Diamonds.net, Jan. 7, 1/4p.Africa, GuineaNews item - Stellar
DM1502-0579
2015
Diamonds.netWDC website posts system of warranties guidelines.Diamonds.net, Jan.7, 1/4p.TechnologyNews item - WDC
DM1502-0580
2015
Diamonds.netRio Tinto's 4 Q diamond production -37%. Argyle and DiavikDiamonds.net, Jan. 20, 1/4p.Australia, Canada, Northwest TerritoriesNews item - Rio Tinto
DM1502-0581
2015
Diamonds.netAdvanced HPHT takes lab grown diamonds to new level. One carat flawlessDiamonds.net, Jan. 20, 1/4p.TechnologyNews item - Diamaz International
DM1502-0582
2015
Diamonds.netLucapa receives $ 15 m bridge financing. LuloDiamonds.net, Jan. 23, 1/4p.Africa, AngolaNews item - Lucapa
DM1502-0583
2015
Diamonds.netOkavango Diamond Company completed first year in business.Diamonds.net, Jan. 23, 1/4p.Africa, BotswanaNews item - Okavango
DM1502-0584
2015
Diamonds.netPetra's 1 H production -2% to 1.6 m carats.Diamonds.net, Jan. 26, 1/4p.Africa, South AfricaNews item - Petra
DM1502-0585
2015
Diamonds.netRio Tinto publishes 17 select diamantaires for 2015.Diamonds.net, Jan. 26, 1/4p.GlobalNews item - Rio Tinto
DM1503-0586
2015
Diamonds.netGIA revises colored stone reports.Diamonds.net, Jan. 29, 1/4p.TechnologyNews item - GIA
DM1503-0587
2015
Diamonds.netAlrosa plans 2015 production +5% to 40 m carats.Diamonds.net, Jan. 29, 1/4p.RussiaNews item - Alrosa
DM1503-0588
2015
Diamonds.netGem Diamonds Letseng sales - 10% in 4Q.Diamonds.net, Jan. 27, 1p.Africa, LesothoNews item - Gem Diamonds
DM1503-0589
2015
Diamonds.netDe Beers January sight estimated at $ 450 M.Diamonds.net, Jan. 27, 1p.GlobalNews item - De Beers
DM1503-0590
2015
Diamonds.netDiamondCorp reports $ 1.4 m sales in 2014.Diamonds.net, Feb. 1, 1/4p.Africa, South AfricaNews item - DiamondCorp
DM1503-0591
2015
Diamonds.netUS says Edwards sane enough to stand trial in diamond fraud case.Diamonds.net, Jan. 30, 1/4p.United StatesNews item - CMKM
DM1503-0592
2015
Diamonds.netMinister urges Zimbabwe's youth to take charge of diamond mining. ChiadzwaDiamonds.net, Jan 30, 1/4p.Africa, ZimbabweNews item - legal
DM1503-0593
2015
Diamonds.netNew Zimbabwe tax scheme makes Murowa unprofitable.Diamonds.net, Jan. 30, 1/4p.Africa, ZimbabweNews item - legal
DM1503-0594
2015
Diamonds.netHeavy traffic expected on Canada's diamond ice road.Diamonds.net, Feb. 3, 1/4p.Canada, Northwest TerritoriesNews item - ice road
DM1503-0595
2015
Diamonds.netAlrosa expects to sell 2 m carats from inventory in 2015.Diamonds.net, Feb. 4, 1/4p.RussiaNews item - Alrosa
DM1503-0596
2015
Diamonds.netAlrosa, Israel sign cooperation agreement… exchange of expertiseDiamonds.net, Feb. 9, 1/4p.Russia, Europe, IsraelNews item - Alrosa
DM1503-0597
2015
Diamonds.netMinister is unimpressed with diamond miners, tells NGOs to stay out of politics.Diamonds.net, Feb. 9, 1/4p.Africa, ZimbabweNews item - legal
DM1503-0598
2015
Diamonds.netKennady Diamonds private placement to raise $ 16 m.Diamonds.net, Feb. 9, 1/4p.Canada, Northwest TerritoriesNews item - Kennady
DM1503-0599
2015
Diamonds.netNorth Arrow's drilling program is underway at the Pikoo diamond project.Diamonds.net, Feb. 11, 1/4p.Canada, SaskatchewanNews item - North Arrow
DM1503-0600
2015
Diamonds.netAlrosa relaxes client sales volume requirements but not prices.Diamonds.net, Feb. 11, 1/4p.RussiaNews item - Alrosa
DM1503-0601
2015
Diamonds.netRio Tinto's diamond revenue +6 % to $901 m in 2014.Diamonds.net, Feb. 12, 1/4p.GlobalNews item - Rio Tinto
DM1503-0602
2015
Diamonds.netStable rough diamond production.Diamonds.net, Feb. 6, 2p.GlobalNews item - production
DM1503-0603
2015
Diamonds.netDe Beers profit, revenue soar in 2014. 74% jump to $ 923 million.Diamonds.net, Feb. 13, 1/4p.GlobalNews item - De Beers
DM1503-0604
2015
Diamonds.netSotheby's to offer 100 carat emerald cut diamond at April auction. Dubbed the "Ultimate emerald cut diamond". De Beers stone mined in southern Africa.Diamonds.net, Feb. 13, 1/4p.TechnologyNews item - diamond notable
DM1503-0605
2015
Diamonds.netDiamondCorp secures wage agreement for Lace mine workers.Diamonds.net, Feb. 18,1 /4p.Africa, South AfricaNews item - DiamondCorp
DM1503-0606
2015
Diamonds.netDiavik Diamond Mines, Crossworks Manufacturing sponsor Yellowknife Gala.Diamonds.net, Feb. 20, 1/4p.Canada, Northwest TerritoriesNews item - Diavik
DM1503-0607
2015
Diamonds.netAlrosa seeks to buy 33% of Catoca production.Diamonds.net, Feb. 19, 1/4p.Africa, Angola, RussiaNews item - Alrosa
DM1504-0608
2015
Diamonds.netLucapa clears bridge loan requirements and raises $ 5 million.Diamonds.net, Mar.3, 1p.Africa, AngolaNews item - Lucapa
DM1504-0609
2015
Diamonds.netAverage rough prices drop for Trans Hex.Diamonds.net, Mar.3, 1/4p.Africa, South AfricaNews item - Trans Hex
DM1504-0610
2015
Diamonds.netGIA & De Beers to speak on synthetic diamonds March 22. Panel discussion at GIADiamonds.net, Mar.3, 1/4p.United StatesNews item - synthetics
DM1504-0611
2015
Diamonds.netDe Beers Feb. sight estimated at $ 550 million.Diamonds.net, Mar. 3, 1/4p.GlobalNews item - De Beers
DM1504-0612
2015
Diamonds.netZimbabwe prepares for no diamond revenue in 2015.Diamonds.net, Mar. 6, 1/4p.Africa, ZimbabweNews item - legal
DM1504-0613
2015
Diamonds.netDiamond miners meet to set up consumer promotion body. Rio Tinto, De Beers, Alrosa, Petra, Gem, Lucara, Dominion, LuKoilDiamonds.net, Mar. 9, 1/4p.GlobalNews item - promo
DM1504-0614
2015
Diamonds.netAlrosa feels weaker demand, sizable inventory levels in the pipeline.Diamonds.net, Mar. 10, 1/4p.RussiaNews item - Alrosa
DM1504-0615
2015
Diamonds.netChidhakwa's plan creates just one diamond miner in Marange.Diamonds.net, Mar. 13, 1/4p.Africa, ZimbabweNews item - legal
DM1504-0616
2015
Diamonds.netTurkey targets growth in diamond trading.Diamonds.net, Mar. 13, 1/4p.Europe, TurkeyNews item - jewellery
DM1504-0617
2015
Diamonds.netAntwerp diamond industry launches offensive in Latin America. Brazil in particular.Diamonds.net, Mar. 11, 1p.South America, BrazilNews item - markets
DM1504-0618
2015
Diamonds.netSarine debuts its profile technology.Diamonds.net, Mar. 16, 1/4p.TechnologyNews item - Sarine
DM1504-0619
2015
Diamonds.netRussian diamond sales unaffected by economic crisis.Diamonds.net, Mar. 16, 1/4p.RussiaNews item - Alrosa
DM1504-0620
2015
Diamonds.netZimbabwe lost $ 12 billion to illegal multinational business practices.Diamonds.net, Mar. 18, 1/4p.Africa, ZimbabweNews item - legal
DM1504-0621
2015
Diamonds.netDe Beers upgrades DiamondView.Diamonds.net, Mar. 18, 1/4p.TechnologyNews item - DiamondView
DM1504-0622
2015
Diamonds.netGem Diamonds profit +57% to $ 33 m in 2014.Diamonds.net, Mar. 17, 1/4p.Africa, LesothoNews item - Gem Diamonds
DM1504-0623
2015
Diamonds.netFancy Color Research Foundation launches mobile website.Diamonds.net, Mar. 19, 1/4p.TechnologyNews item - FCRF
DM1504-0624
2015
Diamonds.netAlrosa reports liss in 2014, revenu + 23% ( foreign exchange loss)Diamonds.net, Mar. 23, 1/4p.RussiaNews item - Alrosa
DM1504-0625
2015
Diamonds.netYellow diamond leads Sotheby's HK spring sale.Diamonds.net, Mar. 23, 1/4p.GlobalNews item - diamond notable
DM1504-0626
2015
Diamonds.netJournalist faces defamation trial for exposing Angolan diamonds abuses. Marquis de MoraisDiamonds.net, Mar. 22, 1p.Africa, AngolaNews item - legal
DM1504-0627
2015
Diamonds.netDe Beers to open first diamond grading institute in Surat.Diamonds.net, Mar. 23, 1/4p.IndiaNews item - De Beers
DM1504-0628
2015
Diamonds.netMerlin Diamonds receives $ 5 million to restart production. ( Govt tax refund).Diamonds.net, Mar. 23, 1/4p.AustraliaNews item - Merlin
DM1504-0629
2015
Diamonds.netAngolan court slaps additional charges on Marques de Morais ( exposed corruption in diamond industry in Angola).Diamonds.net, Mar. 25, 1/4p.Africa, AngolaNews item - legal
DM1504-0630
2015
Diamonds.netGA adopts Sarine's Instructor as standard software.Diamonds.net, Mar. 25, 1/4p.TechnologyNews item - Sarine
DM1504-0631
2015
Diamonds.netDiamond smuggling thrives in CAR.Diamonds.net, Mar. 25, 1/4p.Africa, Central African RepublicNews item - legal
DM1505-0632
2015
Diamonds.netTeeling says diamonds shine in a resource world filled with gloom.Diamonds.net, Mar. 27, 1/4p.GlobalNews item - Botswana Diamonds
DM1505-0633
2015
Diamonds.netStellar Diamonds narrows loss, seeks to raise $ 20 m.Diamonds.net, Mar. 27, 1/4p.Africa, Guinea, Sierra LeoneNews item - Stellar
DM1505-0634
2015
Diamonds.netABN Amro … diamond industry lacks bankability, not liquidity.Diamonds.net, Mar. 27, 1/4p.GlobalNews item - ABN Amro
DM1505-0635
2015
Diamonds.netABN AMRO returns to India.Diamonds.net, Mar. 26, 1/4p.IndiaNews item - ABN Amro
DM1505-0636
2015
Diamonds.netDe Beers announces 84 sightholders.Diamonds.net, Mar. 31, 1/4p.GlobalNews item - De Beers
DM1505-0637
2015
Diamonds.netRefusals exceed 30% at De Beers March sight.Diamonds.net, Mar. 31, 1/4p.GlobalNews item - De Beers
DM1505-0638
2015
Diamonds.netBelgian court returns diamonds to Zimbabwe. Diamonds.net, Mar. 31, 1/4p.Africa, Zimbabwe, BelgiumNews item - legal
DM1505-0639
2015
Diamonds.netGIA's Dreams of Diamonds exhibit comes to southern California. Seven of world's finest diamond houses to showcase exceptionally rare diamonds……Diamonds.net, Apr. 2, 1/4p.United States, CaliforniaNews item - GIA exhibit
DM1505-0640
2015
Diamonds.netZimbabwe's Vice President Mnangagwa colluded with the army and Chinese .. Accused of stealing diamonds.Diamonds.net, Apr. 1, 1/4p.Africa, ZimbabweNews item - legal
DM1505-0641
2015
Diamonds.netProduction drops over refinancing difficulty in 2014. Diamonds.net, Apr. 1, 1/4p.Russia, YakutiaNews item - Alrosa
DM1505-0642
2015
Diamonds.netMugabe taps reserve bank to stop diamond smuggling.Diamonds.net, Apr. 4, 1/4p.Africa, ZimbabweNews item - legal
DM1505-0643
2015
Diamonds.netContrasting quarters … 2014 and 2015. Cause and effect.Diamonds.net, Apr. 4, 1p.GlobalNews item - prices
DM1505-0644
2015
Diamonds.netChidhakwa faces pressure to deliver diamond royalties.Diamonds.net, Apr. 9, 1/4p.Africa, ZimbabweNews item - legal
DM1505-0645
2015
Diamonds.netLucapa recovers a 63 ct diamond from Lulo.Diamonds.net, Apr. 17, 1/4p.Africa, AngolaNews item - Lucapa
DM1505-0646
2015
Diamonds.netPetra's revenue - 41% to $ 96 m in 3 Q.Diamonds.net, Apr. 16, 1/4p.Africa, South AfricaNews item - Petra
DM1505-0647
2015
Diamonds.netSeveralmaz appoints Pismenny as CEO. Diamonds.net, Apr. 16, 1/4p.Russia, Kola Peninsula, ArchangelNews item - Severalmaz
DM1505-0648
2015
Diamonds.netDiamcor's rough sale achieves $ 842 K ( Krone-Endora)Diamonds.net, Apr. 15, 1/4p.Africa, South AfricaNews item - Diamcor
DM1505-0649
2015
Diamonds.netNGOs urge Zimbabwe to consult with stakeholders in Marange merger.Diamonds.net, Apr. 15, 1/4p.Africa, ZimbabweNews item - legal
DM1505-0650
2015
Diamonds.netOGI debuts symmetry leakage technology. Diamonds.net, Apr. 20, 1/4p.TechnologyNews item - OGI
DM1505-0651
2015
Diamonds.netInvestigators probe Marange diamond firm Jinan for transferring $ 546 million.Diamonds.net, Apr. 17, 1/4p.Africa, ZimbabweNews item - Jinan
DM1505-0652
2015
Diamonds.netLucapa's third sale of Lulo production achieves $ 790K.Diamonds.net, Apr. 22, 1/4p.Africa, AngolaNews item - Lucapa
DM1505-0653
2015
Diamonds.netAlrosa's first quarter diamond production + 14%.Diamonds.net, Apr. 21, 1/4p.RussiaNews item - Alrosa
DM1506-0654
2015
Diamonds.netPetra Diamonds launches $300 miln notes issue to fund Cullinan construction.Diamonds.net, Apr. 24, 1/4p.Africa, South AfricaNews item - Petra
DM1506-0655
2015
Diamonds.netZimbabwe diamond centre to open in phases ( machinery sourced from India).Diamonds.net, Apr. 24, 1/4p.Africa, ZimbabweNews item - Diamond Centre
DM1506-0656
2015
Diamonds.netResidents fear consolidation releases Marange firms from broken promises.Diamonds.net, Apr. 23, 1/4p.Africa, ZimbabweNews item - Marange
DM1506-0657
2015
Diamonds.netBank executives tell diamond industry that risk hinders financing.Diamonds.net, Apr. 23, 1/4p.GlobalNews item - economics
DM1506-0658
2015
Diamonds.netDiamcor achieves $ 5 m in revenue from Krone-Endora since 2013.Diamonds.net, Apr. 29, 1/4p.Africa, South AfricaNews item - Diamcor
DM1506-0659
2015
Diamonds.netDebmarine names new vessel after Nujoma.Diamonds.net, Apr. 28, 1/4p.Africa, NamibiaNews item - Debmarine
DM1506-0660
2015
Diamonds.netScio Diamond to double production levels. Diamonds.net, Apr. 27, 1/4p.TechnologyNews item - Scio
DM1506-0661
2015
Diamonds.netLace mine to ramp up production in second half of 2015.Diamonds.net, Apr. 30, 1/4p.Africa, South AfricaNews item - DiamondCorp
DM1506-0662
2015
Diamonds.netDisciplined diamantaires ….Diamonds.net, May 1, 1/4p.GlobalNews item - legal
DM1506-0663
2015
Diamonds.netZimbabwe's local cutters face total lack of supply.Diamonds.net, May 7, 1/4p.Africa, ZimbabweNews item - cutting
DM1506-0664
2015
Diamonds.netUnchecked private jets deliver Marange diamonds to Dubai, Hong Kong.Diamonds.net, May 6, 1/4p.Africa, ZimbabweNews item - Marange
DM1506-0665
2015
Diamonds.netMarket correction: diamond markets under pressure. Martin Rapaport discussion.Diamonds.net, May 8, 8p.GlobalNews item - prices and markets
DM1506-0666
2015
Diamonds.netLucara's revenue -10%, profit +18% in 1Q. KaroweDiamonds.net, May 12, 1/4p.Africa, BotswanaNews item - Lucara
DM1506-0667
2015
Diamonds.netVictor mine's royalties total $ 226 for the 2013 and 2014 period.Diamonds.net, May 12, 1/4p.Canada, OntarioNews item - De Beers
DM1506-0668
2015
Diamonds.netZimbabwe's production value -23% in 2014 to $ 350 million -Marange Diamonds.net, May 15, 1/4p.Africa, ZimbabweNews item - economics
DM1506-0669
2015
Diamonds.netZimbabwe's green diamonds remain a risk for U.S. traders.Diamonds.net, May 13, 1/4p.Africa, ZimbabweNews item - KP
DM1506-0670
2015
Diamonds.netZimbabwe's diamond mining consolidation plan in limbo.Diamonds.net, May 18, 1/4p.Africa, ZimbabweNews item - legal
DM1506-0671
2015
Diamonds.netU.S. reiterates rough diamond suspension on Venezuela, CAR.Diamonds.net, May 18, 1/4p.Africa, Central African Republic, South America, VenezuelaNews item - KP
DM1506-0672
2015
Diamonds.netShore Gold to raise $ 2 mill in private placement. OrionDiamonds.net, May 20, 1/4p.Canada, SaskatchewanNews item - Shore Gold
DM1506-0673
2015
Diamonds.netLucapa's fourth parcel sale from Lulo generates $ 2m.Diamonds.net, May 19, 1/4p.Africa, AngolaNews item - Lucapa
DM1506-0674
2015
Diamonds.netDominion Diamonds's 1 Q rough diamond sales+ 7%.Diamonds.net, May 22, 1/4p.Canada, Northwest TerritoriesNews item - Dominion
DM1507-0675
2015
Diamonds.netIGI certifies 10 carat diamond grown with new technology. ( New Diamond Technology lab Russia fashioned from 32.36 carat man made rough)Diamonds.net, May 26, 1/4p.TechnologyNews item - New Diamond Technology LLC
DM1507-0676
2015
Diamonds.netStellar Diamonds achieved $ 505,000 from its recent sale of rough diamonds from the Baoule project in Guinea.Diamonds.net, May 28, 1/4p.Africa, GuineaNews item - Stellar
DM1507-0677
2015
Diamonds.netPhillippe Mellier's speech transcript from JCK talks series.Diamonds.net, May 30, 1/4p.GlobalNews item - De Beers
DM1507-0678
2015
Diamonds.netDe Beers re-launch 'A diamond is forever' campaign.Diamonds.net, May 29, 1/4p.GlobalNews item - De Beers
DM1507-0679
2015
Diamonds.netDominion launches CanadaMark B2B trading platform.Diamonds.net, June 2, 1/4p.Canada, Northwest TerritoriesNews item - Dominion
DM1507-0680
2015
Diamonds.netOkavango diamond sales volume -20% so far in 2015.Diamonds.net, June 1, 1/4p.Africa, BotswanaNews item - Okavango
DM1507-0681
2015
Diamonds.netRockwell's revenue +19%, loss widens 6%.Diamonds.net, June 1, 1/4p.Africa, South AfricaNews item - Rockwell
DM1507-0682
2015
Diamonds.netDiamondCorp raises $ 5 m., proposes another $ 3 m 'open offer' placement. LaceDiamonds.net, June 5, 3p.Africa, South AfricaNews item - DamondCorp
DM1507-0683
2015
Diamonds.netLucapa ramping up Angola alluvial production, kimberlite exploration.Diamonds.net, June 5, 1/4p.Africa, AngolaNews item - Lucapa
DM1507-0684
2015
Diamonds.netTrans Hex Group FY revenue +35%, profit soars.Diamonds.net, June 4, 1/4p.Africa, South AfricaNews item - Trans Hex
DM1507-0685
2015
Diamonds.netWeak ruble boosts Alrosa revenue, profit in 1 Q.Diamonds.net, June 4, 1/4p.RussiaNews Item - Alrosa
DM1507-0686
2015
Diamonds.netIllegal rough trade flourishes despite CAR's embargo.Diamonds.net, June 8, 1/4p.Africa, Central African RepublicNews item - legal
DM1507-0687
2015
Diamonds.netAWDC, diamond admin. Of China sign cooperative agreement.Diamonds.net, June 4, 1/4p.China, BelgiumNews item - AWDC
DM1507-0688
2015
Diamonds.netConfidence in the diamond dream. ForevermarkDiamonds.net, June 12, 1/4p.GlobalNews item - De Beers
DM1507-0689
2015
Diamonds.netMustang Resources recovers diamonds in Mozambique.Diamonds.net, June 16, 1/2p.Africa, MozambiqueNews item - Mustang
DM1507-0690
2015
Diamonds.netIsrael's diamond leaders call for reduced rough supply.Diamonds.net, June 16, 1/4p.GlobalNews item - IDE
DM1507-0691
2015
Diamonds.netDiamonds provide ample funding to warlords in CAR.Diamonds.net, June 18, 1/4p.Africa, Central African RepublicNews item - legal
DM1507-0692
2015
Diamonds.netDe Beers June sight estimated at $ 550 million.Diamonds.net, June 18, 1/4p.GlobalNews item - De Beers
DM1507-0693
2015
Diamonds.netShore Gold completes drilling program at Star-Orion South.Diamonds.net, June 17, 1/4p.Canada, SaskatchewanNews item - Shore
DM1507-0694
2015
Diamonds.netZimbabwe turns to Botswana for better managing diamonds.Diamonds.net, June 19, 1/4p.Africa, Zimbabwe, BotswanaNews item - legal
DM1507-0695
2015
Diamonds.netParagon preps share buyback, seeks immediate Mothae acquisition.Diamonds.net, June 19, 1/4p.Africa, LesothoNews item - Paragon
DM1507-0696
2015
Diamonds.netDemand grows for industrial and synthetic diamonds.Diamonds.net, June 19, 1/4p.TechnologyNews item - industrial diamonds
DM1507-0697
2015
Diamonds.netDiamond trade subject to arbitration on color grading standards. Policy sets guidelines to tolerance levels on grading.Diamonds.net, June 21, 1/4p.TechnologyNews item - grading
DM1507-0698
2015
Diamonds.netNamibia reviews terms of venture with De Beers.Diamonds.net, June 22, 1/4p.Africa, NamibiaNews item - De Beers
DM1507-0699
2015
Diamonds.netKennedy Diamonds reports sample grade from Kelvin winter drill program.Diamonds.net, June 22, 1/4p.Canada, Northwest TerritoriesNews item - Kennady
DM1507-0700
2015
Diamonds.netLondon Bourse members gain access to bonded warehouse.Diamonds.net, June 24, 1/4p.Europe, EnglandNews item - bourse
DM1507-0701
2015
Diamonds.netOGI releases Titanium 5X laser cutting system.Diamonds.net, June 23, 1/4p.TechnologyNews item - OGI
DM1507-0702
2015
Diamonds.netAlrosa repays $ 185 m worth of commercial bonds.Diamonds.net, June 23, 1/4p.RussiaNews item - Alrosa
DM1507-0703
2015
Diamonds.netKP leaders stress consensus and bringing CAR, Venezuela back into compliance.Diamonds.net, June 24, 1/4p.Africa, Central African Republic, South America, VenezuelaNews item - KP
DM1507-0704
2015
Diamonds.netMellier says Namibia's new diamond sales terms are satisfactory.Diamonds.net, June 24, 1/4p.Africa, NamibiaNews item - De Beers
DM1508-0705
2015
Diamonds.netRapaport presents industry insights, Lussier explains 'The Diamond Dream'.Diamonds.net, June 25, 1/4p.GlobalNews item - economics
DM1508-0706
2015
Diamonds.netNamdeb CEO leaves post for government position. Inge Zaamwani-KamwiDiamonds.net, July 1, 1/4p.Africa, NamibiaNews item - Namdeb
DM1508-0707
2015
Diamonds.netKimberley Process presents roadmap for CAR compliance.Diamonds.net, June 30, 1p.Africa, Central African RepublicNews item - KP
DM1508-0708
2015
Diamonds.netParagon Diamonds loss widens, Revenue target for 2015 is $ 36 million.Diamonds.net, June 29, 1/4p.Africa, LesothoNews item - Paragon
DM1508-0709
2015
Diamonds.netLarge size diamond market under pressure. Q&A with Amir Tiroche, owner and CEO of Tiroche Diamonds.Diamonds.net, July 3, 1/4p.GlobalNews item - Tiroche
DM1508-0710
2015
Diamonds.netDiamond storytelling… marketing and "A Diamond is Forever".Diamonds.net, July 3, 2p.GlobalNews item - De Beers
DM1508-0711
2015
Diamonds.netIndia to continue importing rough diamonds for now.Diamonds.net, July 7, 1/4p.IndiaNews item - rough
DM1508-0712
2015
Diamonds.netZimbabwe mulls bid for Kimberley Process chairmanship by 2018.Diamonds.net, July 7, 1/4p.Africa, ZimbabweNews item - KP
DM1508-0713
2015
Diamonds.netScio revenue halves, loss narrows to $ 4 million.Diamonds.net, July 6, 1/4p.TechnologyNews item - Scio
DM1508-0714
2015
Diamonds.netBotswana's Okavango diamond sales fell 23% in 1 HDiamonds.net, July 9, 1/4p.Africa, BotswanaNews item - Okavango
DM1508-0715
2015
Diamonds.netSightholders can defer 25% of De Beers July supply.Diamonds.net, July 9, 1p.GlobalNews item - De Beers
DM1508-0716
2015
Diamonds.netHRD discovers hard-to-detect synthetic rough diamonds: quick take.Diamonds.net, July 13, 1/4p.TechnologyNews item - HRD Lab
DM1508-0717
2015
Diamonds.netDiamond Hallmarketing seeks to make its mark.Diamonds.net, July 17, 2p.GlobalNews item - Hallmarking
DM1508-0718
2015
Diamonds.netPeregrine Diamonds begins summer development program at Chidliak.Diamonds.net, July 21, 1/4p.Canada, Nunavut, Baffin IslandNews item - Peregrine
DM1508-0719
2015
Diamonds.netNamibia to introduce independent rough diamond sales.Diamonds.net, July 21, 1/4p.Africa, NamibiaNews item - De Beers
DM1508-0720
2015
Diamonds.netAlrosa's 1 H rough diamond sales drop 22 %: quick take.Diamonds.net, July 21, 1/4p.RussiaNews item - Alrosa
DM1508-0721
2015
Diamonds.netDiamcor generates sales of $ 455K in 1 Q. Krone-EndoraDiamonds.net, July 20, 1/4p.Africa, South AfricaNews item - Diamcor
DM1508-0722
2015
Diamonds.netVillagers confront EMA Board about diamond mining pollution.Diamonds.net, July 20, 1/4p.Africa, ZimbabweNews item - EMA
DM1508-0723
2015
Diamonds.netSeeking a better diamond future. Comments from Lieberherr Rio Tinto Diamonds.Diamonds.net, July 17, 1p.GlobalNews item - Rio Tinto
DM1508-0724
2015
Diamonds.netNew synthetic detector to be shown at HK September show: Quick Take Diamonds.net, July 22, 1/4p.TechnologyNews item - Diamond Services
DM1508-0725
2015
Diamonds.netSurat diamond bourse project put on hold.Diamonds.net, July 22, 1/4p.IndiaNews item - Surat
DM1508-0726
2015
Diamonds.netMbada's security guards unleash dogs on illegal panners.Diamonds.net, July 24, 1/4p.Africa, ZimbabweNews item - Mbada
DM1508-0727
2015
Diamonds.netThe futility of chasing rough shadows.Diamonds.net, July 24, 1/4p.GlobalNews item - De Beers
DM1508-0728
2015
Diamonds.netAlrosa has shifted operations at the iconic Udachnay mine…. Opened in June 1955 ..Alrosa's Largest open pit 1,600 X 2,000 m and depth 640 m. 350 million tons of ore containing $ 80 Billion worth mined diamonds.Diamonds.net, July 27, 1/4p.Russia, YakutiaNews item - Alrosa
DM1509-0729
2015
Diamonds.netUnique volcano diamonds found in Russian Far East. TolbachikDiamonds.net, July 27, 1/4p.Russia, KamchatkaNews item - Tolbachik
DM1509-0730
2015
Diamonds.netGem Diamonds 1 H revenue falls 28%.Diamonds.net, July 30, 1/4p.Africa, Lesotho, BotswanaNews item - Gem Diamonds
DM1509-0731
2015
Diamonds.netFipke joins Dunnedin Ventures as company advisor. KahunaDiamonds.net, July 30, 1/4p.Canada, NunavutNews item - Dunnedin
DM1509-0732
2015
Diamonds.netGokhran's rough auction achieves $ 479 per carat.Diamonds.net, July 30, 1/4p.RussiaNews item - Gokhran
DM1509-0733
2015
Diamonds.netZimbabwe to consolidate Marange miners by end of 2015 ( seven companies)Diamonds.net, July 29, 1/4p.Africa, ZimbabweNews item - Marange
DM1509-0734
2015
Diamonds.netRussia weighs establishing rough diamond exchange.Diamonds.net, July 29, 1/4p.RussiaNews item - bourse
DM1509-0735
2015
Diamonds.netLucapa raises $ 3 million for Lulo, postpones rough sale.Diamonds.net, July 27, 1/4p.Africa, AngolaNews item - Lucapa
DM1509-0736
2015
Diamonds.netKao mine large diamond tender begins in New York.Diamonds.net, Aug. 3, 1/4p.Africa, LesothoNews item - Namakwa, Storm Mountain, Fusion, I Hennig
DM1509-0737
2015
Diamonds.netGem International Resources seeks stake in Angola's Dala diamond concession.Diamonds.net, Aug. 3, 1/4p.Africa, AngolaNews item - Gem Diamonds
DM1509-0738
2015
Diamonds.netState Diamond Trader seeks partners for growth.Diamonds.net, July 31, 1/4p.Africa, South AfricaNews item - State Diamond Trader
DM1509-0739
2015
Diamonds.netEllendale mine worker accuses Kimberley Diamonds of unsafe practices.Diamonds.net, Aug. 5, 1/4p.AustraliaNews item - Kimberley Diamonds
DM1509-0740
2015
Diamonds.netRio Tinto diamond revenue -23% to $ 331 million in H1.Diamonds.net, Aug. 6, 1/4p.GlobalNews item - Rio Tinto
DM1509-0741
2015
Diamonds.netLucara cuts production outlook as 2Q revenue, profit plummet. KaroweDiamonds.net, Aug. 13, 1/4p.Africa, BotswanaNews item - Lucara
DM1509-0742
2015
Diamonds.netBotswana diamond producers cut 1,000 jobs in past year. MmegiDiamonds.net, Aug, 13, 1/4p.Africa, BotswanaNews item - cutters
DM1509-0743
2015
Diamonds.netWeak diamond sales may fuel Botswana budget deficit.Diamonds.net, Aug. 18, 1/4p.Africa, BotswanaNews item - sales
DM1509-0744
2015
Diamonds.netLucara finds 336 carat diamond at Botswana mine. KaroweDiamonds.net, Aug. 18, 1/4p.Africa, BotswanaNews item - Lucara
DM1509-0745
2015
Diamonds.netNamibia diamond venture pays % 4.6 m dividend to state. NDTCDiamonds.net, Aug. 19, 1/4p.Africa, NamibiaNews item - NDTC
DM1509-0746
2015
Diamonds.netIs diamond demand determined in Beijing and Washington?Diamonds.net, Aug. 20, 1/4p.United States, ChinaNews item - demand
DM1509-0747
2015
Diamonds.netRussia outshines Botswana as world's top diamond producer in 2014.Diamonds.net, Aug. 25, 1/4p.RussiaNews item - Alrosa
DM1509-0748
2015
Diamonds.netStellar says Tongo to produce 1 million carats over 18 years.Diamonds.net, Aug. 24, 1/4p.Africa, Sierra LeoneNews item - Stellar
DM1509-0749
2015
Diamonds.netDe Beers price cuts could top 10% at sight.Diamonds.net, Aug. 25, 1/4p.GlobalNews item - De Beers
DM1509-0750
2015
Diamonds.netBlue diamonds drive color index higher in 2Q. Fancy Color diamond index ( FCDI tm)Diamonds.net, Aug. 25, 1/4p.GlobalNews item - Blue diamonds
DM1509-0751
2015
Diamonds.netSightholders react to price cuts at $250M sight…. Mixed reactions.Diamonds.net, Aug. 27, 1/4p.GlobalNews item - De Beers
DM1509-0752
2015
Diamonds.netDe Beers maintains outlook for season amid market turmoil.Diamonds.net, Aug. 26, 1/4p.GlobalNews item - De Beers
DM1510-2016
2015
Diamonds.netGIA plans 2016 for opening for synthetic research centre.Diamonds.net, Sept. 1, 1/4p.United States, New JerseyNews item - GIA
DM1510-2017
2015
Diamonds.netAlrosa 1 Q sales up 20% $875.8 million.Diamonds.net, Aug. 30, 1/4p.RussiaNews item - Alrosa
DM1510-2018
2015
Diamonds.netAlrosa unit diamonds go missing at Gokhran.Diamonds.net, Aug. 30, 1/4p.RussiaNews item - Alrosa
DM1510-2019
2015
Diamonds.netAlrosa may cut diamond prices again as orders fall short.Diamonds.net, Sept. 2, 1/4p.RussiaNews item - Alrosa
DM1510-2020
2015
Diamonds.netLucapa recovers 10 ct plus diamonds from Angola's Lulo site.Diamonds.net, Sept. 3, 1/4p.Africa, AngolaNews item - Lucapa
DM1510-2021
2015
Diamonds.netMwana Africa to raise $ 5.6 million for Klipspringer mine work.Diamonds.net, Sept. 3, 1/4p.Africa, South AfricaNews item - Mwana
DM1510-2022
2015
Diamonds.netNew sightholder KGK opens Botswana factory.Diamonds.net, Sept. 3, 1/4p.Africa, BotswanaNews item - KGK
DM1510-2023
2015
Diamonds.netZimbabwe urged to curb rough diamond exports.Diamonds.net, Sept. 6, 1/4p.Africa, ZimbabweNews item - exports
DM1510-2024
2015
Diamonds.netRussia looks to Shanghai experience for Vladivostok diamond exchange.Diamonds.net, Sept. 6, 1/4p.RussiaNews item - Vladivostok
DM1510-2025
2015
Diamonds.netLucara sets November exceptional stone tender. KaroweDiamonds.net, Sept. 8, 1/4p.Africa, BotswanaNews item - Lucara
DM1510-2026
2015
Diamonds.netIsrael diamond industry readies for anti-money laundering law.Diamonds.net, Sept. 9, 1/4p.Europe, IsraelNews item - legal
DM1510-2027
2015
Diamonds.netDiamond prices pressured by financial market slump.Diamonds.net, Sept. 9, 1/4p.GlobalNews item - prices, supply, demand
DM1510-2028
2015
Diamonds.netCatoca mine diamond sales rise 1% in 2014.Diamonds.net, Sept. 9, 1/4p.Africa, AngolaNews item - Endiama
DM1510-2029
2015
Diamonds.netKimberley process: where is it now? Diamonds.net, Sept. 9, 2p.GlobalNews item - KP
DM1510-2030
2015
Diamonds.netEx-Kimberley Diamonds boss arrested over yellow diamond price reports. Alexander AlexanderDiamonds.net, Sept. 16, 1/4p.AustraliaNews item - Kimberley Diamonds
DM1510-2031
2015
Diamonds.netDe Beers growth highlights India as counter to flat growth.Diamonds.net, Sept. 21, 1/4p.IndiaNews item - De Beers
DM1510-2032
2015
Diamonds.netBotswana and Alrosa start Orapa license work.Diamonds.net, Sept. 21, 1/4p.Africa, BotswanaNew item - Botswana Diamonds, Alrosa
DM1510-2033
2015
Diamonds.netRussia's H1 rough diamond exports slide 16%.Diamonds.net, Sept. 20, 1/4p.RussiaNews item - Alrosa
DM1511-2124
2015
Diamonds.netRio Tinto sets first time India rough auction.Diamonds.net, Sept. 29, 1/4p.IndiaNews item - Rio Tinto
DM1511-2125
2015
Diamonds.netLab grown diamonds set to fill deficit as mined output declines.Diamonds.net, Sept. 29, 1/4p.GlobalNews item - synthetics
DM1511-2126
2015
Diamonds.netFancy vivid pink diamond to list at Christies for $ 23-28 million. 16.08 ctsDiamonds.net, Sept. 29, 1/4p.GlobalNews item - diamond notable
DM1511-2127
2015
Diamonds.netIndia preparing measures to raise direct purchases of Russian rough.Diamonds.net, Sept. 29, 1/4p.Russia, IndiaNews item - rough
DM1511-2128
2015
Diamonds.netIndian diamond consumers need differentiated strategy: De Beers.Diamonds.net, Sept. 29, 1/4p.IndiaNews item - De Beers
DM1511-2129
2015
Diamonds.netBotswana first half rough exports - 15%Diamonds.net, Oct. 1, 1/4p.Africa, BotswanaNews item - Debswana
DM1511-2130
2015
Diamonds.netAlrosa unearths 103 carat diamond at Jubilee pipe.Diamonds.net, Oct. 12, 1/4p.RussiaNews item - Alrosa
DM1511-2131
2015
Diamonds.netDe Beers October rough sales reflect depressed market.Diamonds.net, Oct. 14, 1/4p.GlobalNews item - De Beers
DM1511-2132
2015
Diamonds.netDiamondCorp delays sales due to slow mining progress. LaceDiamonds.net, Oct. 15, 1/4p.Africa, South AfricaNews item - DiamondCorp
DM1511-2133
2015
Diamonds.netSynthetic diamonds: legitimize, don't ostracize.Diamonds.net, Oct. 15, 2p.TechnologyNews item - synthetics
DM1511-2134
2015
Diamonds.netEllendale may be handed back to the local government.Diamonds.net, Oct. 22, 1/4p.AustraliaNews item - Ellendale
DM1511-2135
2015
Diamonds.netSignet inks rough supply deal with Alrosa. A list of Alrosa's clients included.Diamonds.net, Oct. 21, 2p.RussiaNews item - Alrosa
DM1511-2136
2015
Diamonds.netE-commerce startup Worthy raises $ 8 million for diamond, colored gems expansion.Diamonds.net, Oct. 25, 1/2p.GlobalNews item - Worthy
DM1511-2137
2015
Diamonds.netGIA invalidates 1,000 plus grading reports after hackers alter data.Diamonds.net, Oct. 24, 1/2p.GlobalNews item - GIA
DM1511-2138
2015
Diamonds.netDe Beers enables 100% deferrals at November sight.Diamonds.net, Oct. 26, 1/4p.GlobalNews item - De Beers
DM1512-2221
2015
Diamonds.netSouth Africa told its lagging diamond industry needs a boost.Diamonds.net, Oct. 29, 1/4p.Africa, South AfricaNews item - economics
DM1512-2222
2015
Diamonds.netBotswana 3 Q rough exports -41%.Diamonds.net, Nov. 3, 1/4p.Africa, BotswanaNews item - exports
DM1512-2223
2015
Diamonds.netArgyle pink tender results come in as Leibish wins 26 stones.Diamonds.net, Nov. 3, 1/4p.AustraliaNews item - Argyle
DM1512-2224
2015
Diamonds.netSarine Technologies swings to loss in 3Q as revenue plummets 53%.Diamonds.net, Nov. 9, 1/4p.TechnologyNews item - Sarine
DM1512-2225
2015
Diamonds.netDe Beers November sight slumps to estimated $ 70 million.Diamonds.net, Nov. 11, 2p.GlobalNews item - De Beers
DM1512-2226
2015
Diamonds.netRio Tinto says Karelian's Finland find is diamond making material.Diamonds.net, Nov. 11, 1/4p.Europe, FinlandNews item - Karelian
DM1512-2227
2015
Diamonds.netMurowa mine working to boost production after Rio Tinto exit.Diamonds.net, Nov. 11, 1/4p.Africa, ZimbabweNews item - Murowa Diamonds
DM1512-2228
2015
Diamonds.netUK's Paragon Diamond shares, listed on UK alternative has had its shares temporarily suspended amid financial 'uncertainty'.Diamonds.net, Nov. 17, 1/4p.Africa, LesothoNews item - Paragon
DM1512-2229
2015
Diamonds.netLab-grown diamond producer Scio's 2Q revenue doubles, net loss widens 8%.Diamonds.net, Nov. 17, 1/4p.TechnologyNews item - Scio
DM1512-2230
2015
Diamonds.netRio Tinto carries out first shipment of rough diamonds to BDB's special notified zone. BharatDiamonds.net, Nov. 16, 1/4p.IndiaNews item - Rio Tinto
DM1512-2231
2015
Diamonds.netIndia's GJEPC plans advertising push with global miners to revive diamond trade.Diamonds.net, Nov. 17, 1/4p.IndiaNews item - GJEPC
DM1512-2232
2015
Diamonds.netHistoric diamonds put Lucara in enviable spotlight. Second and Sixth largest diamonds in history.Diamonds.net, Nov. 19, 3p.Africa, BotswanaNews item - Lucara
DM1512-2233
2015
Diamonds.netAlrosa revises sales budget, keeps production plan unchanged.Diamonds.net, Nov. 23, 1/4p.RussiaNews item - Alrosa
DM1512-2234
2015
Diamonds.netDe Beers shareholders to meet on diamond prices.Diamonds.net, Nov. 23, 1/4p.Africa, BotswanaNews item - De Beers
DM1512-2235
2015
Diamonds.netDominion sales -53% as average price drop at Ekati.Diamonds.net, Nov. 22, 1/4p.Canada, Northwest TerritoriesNews item - Dominion
DM1512-2236
2015
Diamonds.netAustralia's Mustang Resources raises $ 4.1 million to progress Mozambique projects. Save RiverDiamonds.net, Nov. 25, 1/4p.Africa, MozambiqueNews item - Mustang
DM1512-2237
2015
Diamonds.netTiffany's 3Q revenue -2% as strong dollar mutes sales.Diamonds.net, Nov. 24, 1p.GlobalNews item - Tiffany
DM1512-2238
2015
Diamonds.netRapaport calls for resignation of De Beers CEO. Diamonds.net, Nov. 24, 1/2p.GlobalNews item - De Beers
DM1512-2239
2015
Diamonds.netHow Botswana will find independence. 50 yearsDiamonds.net, Nov. 26, 1/4p.Africa, BotswanaNews item - history
DM1512-2240
2015
Diamonds.netMajority of diamonds in GIA hacking case still not returned, 175 of 1,042 only so far.Diamonds.net, Nov. 26, 1/4p.TechnologyNews item - GIA
DM1512-2241
2015
Diamonds.netParagon's nominated advisor quits as London shares remain suspended.Diamonds.net, Nov. 26, 1/4p.Africa, LesothoNews item - Paragon
DM1512-2242
2015
Diamonds.netZimbabwe government urged to float consolidated diamond company.Diamonds.net, Nov. 26, 1/4p.Africa, ZimbabweNews item - legal
DM1502-0540
2014
DIB OnlineTrust is a two way street…. Israel's diamond industry works to fortify local polishing sector. Diamond Intelligence Brief, No. 844, Dec. 31, 1p.IndiaNews item - polishing
DM1505-0754
2015
DIB OnlineModular tailings plant planned for Debswana's Letlhakane mine site.diamondintelligence.com, 1/2p.Africa, BotswanaNews item - Debswana
DM1507-0541
2015
DIB OnlineKPCS intercessional: Zimbabwe on the agenda again. Diamondintelligence.com, June 24, 1/4p.Africa, ZimbabweNews item - KP
DM1507-0542
2015
DIB OnlineKennady's Kelvin produces excellent results - sample grade 2.74 ctDiamondintelligence.com, June 24, 1/4p.Canada, Northwest TerritoriesNews item - Kennady
DM1507-0543
2015
DIB OnlineSunland Minerals' Botswana exploration promising.Diamondintelligence.com, June 18, 1/4p.Africa, BotswanaNews item - Botswana Diamonds, Alrosa
DM1508-0755
2015
DIB OnlineDe Beers mining production down 6% in Q2DIB Online, July 16, 1p.GlobalNews item - De Beers
DM1508-0756
2015
DIB OnlineNamibia's Trustco may acquire diamond mine and polishing factory in Namibia. Kunene Huso and NNDCDIB Online, July 13, 1/2p.Africa, NamibiaNews item - Trustco
DM1508-0757
2015
DIB OnlineTalks stalled between Dominion and Canada's Union of Northern Workers. DIB Online, July 13, 1/2p.Canada, Northwest TerritoriesNews item - Dominion
DM1509-0753
2015
DIB OnlineSierra Leoneons face depletion of existing alluvial deposits. DIB Online, Aug. 11, 1/4p.Africa, Sierra LeoneNews item - alluvials
DM1509-0758
2015
DIB OnlineDominion fiscal Q2 2016 results: diamond sales $ 209.7 million. Ekati and DiavikDIBOnline.com, Aug. 23, 1/4p.Canada, Northwest TerritoriesNews item - Dominion
DM1509-0759
2015
DIB OnlineLarge diamond possibly worth over $ 7 million 'missing' from India's Panna district. ( shallow open pits)DIBOnline.com, No. 861, Aug. 24, 1/4p.IndiaNews item - legal
DS1512-1914
2015
Dickson, J.S.Rare earth elements: global market overview.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov 13-14 2015, pp. 5-12.GlobalRare earths

Abstract: Rare earth elements (REE), as defi ned by the International Union of Pure and Applied Chemistry (IUPAC), include yttrium (Y), scandium (Sc), and the lanthanides, comprising lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), and lutetium (Lu). In the scientifi c community, subdivisions into light (LREE) and heavy (HREE) categories are based on electron confi guration. In this context, LREE include La, Ce, Pr, Nd, Pm, Sm, Eu, and Gd and HREE include Y, Tb, Dy, Ho, Er, Tm, Yb, and Lu (Connelly et al., 2005). Industry commonly refers to LREE as lanthanides from La to Sm, and HREE as lanthanides from Eu to Lu, plus Y (Simandl, 2014). World mine production of rare earth oxides (REO) for 2014 is estimated at approximately 117,000 tonnes, including Y2O3, which accounts for 7000 tonnes of the total (Gambogi, 2015a, b). In 2014, the main producing countries for REE less Y were China, with 86% of worldwide production (Gambogi, 2015a), the United States, India, Australia, Russia, and Thailand (Fig. 1).
DS1502-0054
2015
Dobretsov, N.L., Koulakov, I.Yu., Litasov, K.D., Kukarina, E.V.An integrated model of subduction: contributions from geology, experimental petrology and seismic tomography.Russian Geology and Geophysics, Vol. 56, 1-2, pp. 13-38.MantleSubduction
DS1509-0394
2015
Dobretsov, N.L., Turkina, O.M.Early Precambrian Earth history: plate and plume tectonics and extraterrestrial controls.Russian Geology and Geophysics, Vol. 56, pp. 978-995.MantleSubduction

Abstract: The Hadean and Archean geologic history of the Earth is discussed in the context of available knowledge from different sources: space physics and comparative planetology; isotope geochronology; geology and petrology of Archean greenstone belts (GB) and tonalite-trondhjemite-granodiorite (TTG) complexes; and geodynamic modeling review to analyse plate-tectonic, plume activity, and impact processes. Correlation between the age peaks of terrestrial Hadean-Early Archean zircons and late heavy bombardment events on the Moon, as well as the Hf isotope composition of zircons indicating their mostly mafic sources, hint to an important role of impact processes in the Earth’s history between 4.4 and 3.8 Ga. The earliest continental crust (TTG complexes) formed at 4.2 Ga (Acasta gneisses), while its large-scale recycling left imprint in Hf isotope signatures after 3.75 Ga. The associations and geochemistry of rocks suggest that Archean greenstone belts formed in settings of rifting, ocean floor spreading, subduction, and plume magmatism generally similar to the present respective processes. The Archean history differed in the greater extent of rocks derived from mantle plumes (komatiites and basalts), boninites, and adakites as well as in shorter subduction cycles recorded in alternation of typical calc-alkaline andesite-dacite-rhyolite and adakite series that were generated in a hotter mantle with more turbulent convection and unsteady subduction. The Archean is interpreted as a transient period of small plate tectonics.
DS1507-0309
2015
Dobretsov, N.L., Zedgenizov, D.A., Litasov, K.D.Evidence for and consequences of the "hot" subduction model.Doklady Earth Sciences, Vol. 461, 1, pp. 517-521.MantleSubduction
DS1511-1832
2015
Doglioni, C., Anderson, D.L.Top-driven asymmetric mantle convection.Geological Society of America Special Paper, No. 514, pp. SPE514-05.MantleConvection

Abstract: The role of decoupling in the low-velocity zone is crucial for understanding plate tectonics and mantle convection. Mantle convection models fail to integrate plate kinematics and thermodynamics of the mantle. In a first gross estimate, we computed at >300 km3/yr the volume of the plates lost along subduction zones. Mass balance predicts that slabs are compensated by broad passive upwellings beneath oceans and continents, passively emerging at oceanic ridges and backarc basins. These may correspond to the broad low-wavespeed regions found in the upper mantle by tomography. However, west-directed slabs enter the mantle more than three times faster (~232 km3/yr) than in the opposite east- or northeast-directed subduction zones (~74 km3/yr). This difference is consistent with the westward drift of the outer shell relative to the underlying mantle, which accounts for the steep dip of west-directed slabs, the asymmetry between flanks of oceanic ridges, and the directions of ridge migration. The larger recycling volumes along west-directed subduction zones imply asymmetric cooling of the underlying mantle and that there is an "easterly" directed component of the upwelling replacement mantle. In this model, mantle convection is tuned by polarized decoupling of the advecting and shearing upper boundary layer. Return mantle flow can result from passive volume balance rather than only by thermal buoyancy-driven upwelling.
DC1501-1457
2014
Dolat Ventures Inc.Dolat Ventures Inc. completes corporate restructuring…and Millenium Mining LLC ( subsidiary) has signed a JV to restart diamond mining near Bo, Sierra Leone. Sewa RiverDolat Ventures Inc., Dec. 1, 1p.Africa, Sierra LeoneNews item - press release
DC1501-1458
2014
Dolat Ventures Inc.Moves forward with private investment into diamond mine assets. To restart mining at Bo, Sierra Leone.Dolat Ventures Inc., Dec. 9, 1p.Africa, Sierra LeoneNews item - press release
DC1501-1459
2014
Dolat Ventures Inc.Dolat ventures to reduce outstanding stock.Dolat Ventures Inc., Dec. 12, 1p.Africa, Sierra LeoneNews item - press release
DC1503-1460
2015
Dominion Diamond CorporationDominion Diamond Corporation announces Jay project pre-feasibility study results. 84.6 million carats promoted to mineral reserve… NPV of $ 610 mililon.Dominion Diamond Corporation, Jan. 28, 3p.Canada, Northwest TerritoriesNews item - press release
DC1503-1461
2015
Dominion Diamond CorporationDominon Diamond reports fiscal 2015 fourth quarter and year end sales and production results.Dominion Diamond Corporation, Feb. 23, 5p.Canada, Northwest TerritoriesNews item - press release
DC1504-1462
2015
Dominion Diamond CorporationDominion Diamond Corporation issues updated reserves amd resources statement for the Diavik diamond mine. Dominion Diamond Corporation, Mar. 6, 5p.Canada, Northwest TerritoriesNews item - press release
DC1504-1463
2015
Dominion Diamond CorporationDominion files technical report for the Ekati diamond mine.Dominion Diamond Corporation, Mar. 12, 14p.Canada, Northwest TerritoriesNews item - press release
DC1505-1464
2015
Dominion Diamond CorporationDominion Diamond Corporation files technical report for the Diavik diamond mines.Dominion Diamond Corporation , Mar. 26, 2p.Canada, Northwest TerritoriesNews item - press release
DC1505-1465
2015
Dominion Diamond CorporationDominion Diamond Corporation reports continued strong operating results supporting dividend declaration.Dominion Diamond Corporation , Apr. 8, 4p.Canada, Northwest TerritoriesNews item - press release
DC1505-1466
2015
Dominion Diamond CorporationDominion Diamond Corporation files annual report on Form 40-F with SEC.Dominion Diamond Corporation , Apr. 20, 2p..Canada, Northwest TerritoriesNews item - press release
DC1505-1467
2015
Dominion Diamond CorporationDominion reports Diavik diamond mine first calendar quarter production. Dominion Diamond Corporation , Apr. 21, 5p.Canada, Northwest TerritoriesNews item - press release
DC1506-1468
2015
Dominion Diamond CorporationDominion Diamond Corporation reports fiscal 2016 first quarter sales and production results.Dominion Diamond Corporation, May 21, 5p.Canada, Northwest TerritoriesNews item - press release
DC1507-1469
2015
Dominion Diamond CorporationDominion Diamond Corporation's fiscal 2016 first quarter results to be released Wednesday June 10, 2015.Dominion Diamond Corporation, June 10, 3p.Canada, Northwest TerritoriesNews item - press release
DC1508-1470
2015
Dominion Diamond CorporationDominion Diamond Corporation announces Chairman Robert A. Gannicott to resume duties and Brendan Bell appointed CEO.Dominion Diamond Corporation, July 13, 1p.Canada, Northwest TerritoriesNews item - press release
DC1508-1471
2015
Dominion Diamond CorporationDominion Diamond Corporation reports Diavik diamond mine second calendar quarter production.Dominion Diamond Corporation, July 15, 2p.Canada, Northwest TerritoriesNews item - press release
DC1509-1472
2015
Dominion Diamond CorporationDominion Diamond Corporation fiscal 2016 second quarter sales and production results.Dominion Diamond Corporation, Aug. 20, 5p.Canada, Northwest TerritoriesNews item - press release
DC1510-2344
2015
Dominion Diamond CorporationDominion Diamond Corporation reports fiscal 2016 second quarter results.Dominion Diamond Corporation, Sept. 10, 5p.Canada, Northwest TerritoriesNews item - press release
DC1510-2345
2015
Dominion Diamond CorporationDominion Diamond Corporation announces Sable project preliminary economic assessment results. 11.7 m carats operational synergies with Jay project.Dominion Diamond Corporation, Sept. 10, 2p.Canada, Northwest TerritoriesNews item - press release
DC1511-2378
2015
Dominion Diamond CorporationDominion Diamond Corporation reports Diavik diamond mine third calendar quarter production.Dominion Diamond Corporation, Oct. 15, 7p.Canada, Northwest TerritoriesNews item - press release
DC1512-2430
2015
Dominion Diamond CorporationDominion Diamond reports fiscal 2016 third quarter sales and production results.Dominion Diamond Corporation, Nov. 20, 5p.Canada, Northwest TerritoriesNews item - press release
DS1508-0350
2015
Dongre, A.N., Jacob, D.E., Stern, R.A.Subduction related origin of eclogite xenoliths from the Wajrakarur kimberlite field, Eastern Dharwar craton, southern India: constraints from petrology and geochemistry.Geochimica et Cosmochimica Acta, Vol. 166, pp. 165-188.IndiaDeposit - Wajrakarur
DS1508-0351
2015
Dongre, A.N., Viljoen, K.S., Ma, M.The Pipe-15 kimberlite: a new addition to the Wajrakarur cluster of the Wajrakarur kimberlite field, Eastern Dharwar craton, southern India.Journal of the Geological Society of India, Vol. 86, 1, pp. 71-79.IndiaDeposit - Pipe-15
DS1502-0055
2015
Dorogokupets, P.I., Dymshits, A.M., Sokolova, T.S., Danilov, B.S., Litasov, K.D.The equations of state of forsterite, wadsleyite, ringwoodite, akimotoite, Mg2SiO4 perovskite and post perovskite and phase diagram for the Mg2SiO4 system at pressures of up to 130 Gpa.Russian Geology and Geophysics, Vol. 56, 1-2, pp. 172-189.TechnologyPerovskite
DS1511-1833
2014
Downes, P.J., Bevan, A.W.R., Deacon, G.L.The Kimberley Diamond Company Ellendale diamond collection at the Western Australia Museum.Australian Gemmologist, Vol. 24, 12, pp. 289-293.AustraliaDeposit - Ellendale
DC1502-1474
2015
Dunnedin Ventures Inc.TSX venture exchange approves Kahuna option agreement.Dunnedin Ventures Inc., Jan. 5, 1p.Canada, NunavutNews item - press release
DC1503-1473
2015
Dunnedin Ventures Inc.Dunnedin reports 4.02 carat inferred diamond resource at Khuna.Dunnedin Ventures Inc., Jan. 26, 3p.Canada, NunavutNews item - press release
DC1504-1475
2015
Dunnedin Ventures Inc.Dunnedin increases land position to control additional kimberlites. KahunaDunnedin Ventures Inc., Mar. 2, 1p.Canada, NunavutNews item - press release
DC1505-1476
2015
Dunnedin Ventures Inc.Dunnedin files maiden resource report including additional target for further exploration. Kahuna and NotchDunnedin Ventures Inc., Mar. 31, 1p.Canada, NunavutNews item - press release
DC1506-1477
2015
Dunnedin Ventures Inc.Dunnedin receives land use permits and adds diamond project development expertise. KahunaDunnedin Ventures Inc., May 7, 1p.Canada, NunavutNews item - press release
DC1508-1478
2015
Dunnedin Ventures Inc.Dunnedin announces July mobiliazation and expands scope of project. KahunaDunnedin Ventures Inc., June 29, 2p.Canada, Nunavut, Rankin InletNews item - press release
DC1510-2346
2015
Dunnedin Ventures Inc.Dunnedin provides update on summer diamond exploration and announces non-brokered private placement.Dunnedin Ventures Inc., Aug. 31, 1p.Canada, NunavutNews item - press release
DC1511-2379
2015
Dunnedin Ventures Inc.Dunnedin provides update on kimberlite sample processing. Kahuna and Notch.Dunnedin Ventures Inc., Oct. 8, 1p.Canada, NunavutNews item - press release
DC1512-2431
2015
Dunnedin Ventures Inc.Dunnedin reports 5.34 carats from first 0.82 tonne kimberlite sample.Dunnedin Ventures Inc., Nov. 12, 1p.Canada, QuebecNews item - press release
DC1505-1479
2015
Durango Resources Inc.Durango signs non binding LOI for diamonds in James Bay.Durango Resources Inc., Mar. 24, 1p.Canada, Quebec, Otish MountainsNews item - press release
DC1505-1480
2015
Durango Resources Inc.Durango to focus on gold in the James Bay region. Not to continue LOI for the Lucky 7 diamond property.Durango Resources Inc., Apr. 1, 1p.Canada, QuebecNews item - press release
DS1504-0193
2014
Dvoichenkova, G.P.Mineral formations on natural diamond surface and their destruction using electrochemically modified mineralized water.Journal of Mining Science, Vol. 50, 4, pp. 788-799.TechnologyDiamond morphology - surfaces
DS1510-1765
2014
Dvoichenkova, G.P.Mineral formations on natural diamond surface and their destruction using electrochemically modified mineralized water.Journal of Mining Science, Vol. 50, 4, pp. 788-799.TechnologyDiamond morphology

Abstract: The article describes modeling and analysis of formation, attachment and dissolving of mineral substances on surface of diamond crystals. Based on the thermodynamic analysis and experimental research, the author validates deposition of chemical compounds as the main factor to govern mineral formations on natural diamond surface under contact with mineralized water in the occurrence conditions of kimberlite ore and during mining and processing. The efficiency of electrochemically modified water in dissolving and removal of mineral formations from diamond surface is ascertained.
DS1504-0194
2015
Dymshits, A., Sharygin, I., Litasov, K., Shatskiy, A., Gavryushkin, P., Ohtani, E., Suzuki, A., Funakoshi, K.In situ observation of the pyroxene majorite transition in Na2MgSi5O12 using synchroton radiation and Raman spectroscopy of Na-majorite.American Mineralogist, Vol. 100, pp. 378-384.MantleMajorite
DS1508-0352
2015
Eaton-Magana, S.Comparison of luminescence lifetimes from natural and laboratory irradiated diamonds.Diamond and Related Materials, Vol 58, pp. 94-102.TechnologyDiamond - luminescence
DS1510-1766
2015
Eaton-Magana, S., Ardon, T.Effect of LPHT treatment on natural Type 1A diamonds.GSA Annual Meeting, Paper 300-10, 1p. Abstract only BoothTechnologyLPHT
DS1512-1915
2015
Ebert, K., Brodaric, B.GIS analyses of ice-sheet erosional impacts on the exposed shield of Baffin Island, eastern Canadian Arctic.Canadian Journal of Earth Sciences, Vol. 52, 11, pp. 966-979.Canada, Nunavut, Baffin IslandGeomorphology

Abstract: The erosional impacts of former ice sheets on the low-relief bedrock surfaces of Northern Hemisphere shields are not well understood. This paper assesses the variable impacts of glacial erosion on a portion of Baffin Island, eastern Canadian Arctic, between 68° and 72°N and 66° and 80°W. This tilted shield block was covered repeatedly by the Laurentide Ice Sheet during the late Cenozoic. The impact of ice-sheet erosion is examined with GIS analyses using two geomorphic parameters: lake density and terrain ruggedness. The resulting patterns generally conform to published data from other remote sensing studies, geological observations, cosmogenic exposure ages, and the distribution of the chemical index of alteration for tills. Lake density and terrain ruggedness are thereby demonstrated to be useful quantitative indicators of variable ice-sheet erosional impacts across Baffin Island. Ice-sheet erosion was most effective in the lower western parts of the lowlands, in a west-east-oriented band at around 350-400 m a.s.l., and in fjord-onset zones in the uplifted eastern region. Above the 350-400 m a.s.l. band and between the fjord-onset zones, ice-sheet erosion was not sufficient to create extensive ice-roughened or streamlined bedrock surfaces. The exception — where lake density and terrain ruggedness indicate that ice-sheet erosion had a scouring effect all across the study area — was in an area from Foxe Basin to Home Bay with elevations <400 m a.s.l. These morphological contrasts link to former ice-sheet basal thermal regimes during the Pleistocene. The zone of low glacial erosion surrounding the cold-based Barnes Ice Cap probably represents the ice cap’s greater extent during successive Pleistocene cold stages. Inter-fjord plateaus with few ice-sheet bedforms remained cold-based throughout multiple Pleistocene glaciations. In contrast, zones of high lake density and high terrain ruggedness are a result of the repeated development of fast-flowing, erosive ice in warm-based zones beneath the Laurentide Ice Sheet. These zones are linked to greater ice thickness over western lowland Baffin Island. However, adjacent lowland surfaces with similar elevations of non-eroded, weakly eroded, and ice-scoured shield bedrock indicate that—even in areas of high lake density and terrain ruggedness—the total depth of ice sheet erosion did not exceed 50 m.
DM1508-0760
2015
Ecclestone, C.Tango Mining .. Strategy Oena .. Coverage by analystHallgarten & Company cecclestone @hallgartenco.com, July 6, 16p.Africa, South AfricaNews item - Tango Mining
DS1507-0310
2015
Edwards, S.J., Schellart, W.P., Duarte, J.C.Geodynamic models of continental subduction and obduction of overriding plate forearc oceanic lithosphere on top of continental crust.Tectonics, Vol. 34, 7, pp. 1494-1515.New ZealandSubduction
DM1508-0761
2015
Ehud Arye LaniadoTackling debts & fears in today's diamond market.ehudlaniado.com, June 29, 8p.GlobalNews item - markets
DM1508-0762
2015
Ehud Arye LaniadoDark Clouds loom over the diamond industry.ehudlaniado.com, July 13, 5p.GlobalNews item - economics
DM1508-0763
2015
Ehud Arye LaniadoAntwerp and diamonds: a rocky love story.EAL, July 15, 4p.EuropeNews item - diamond centers -history
DM1508-0764
2015
Ehud Arye LaniadoMiners vs the Midstream: who needs to change?info @ehudlaniado.com, July 27, 5p.GlobalNews item - value chain
DM1509-0765
2015
Ehud Arye LaniadoIndia where it all began.ehudlaniado.com, July 29, 3p.IndiaNews item - history
DM1509-0766
2015
Ehud Arye LaniadoNot a price correction but a market correction.ehudlaniado.com, Aug. 3, 3p.GlobalNews item - markets
DM1509-0767
2015
Ehud Arye LaniadoNew York diamond center.ehudlaniado.com, Aug. 5, 4p.United StatesNews item - history
DM1509-0768
2015
Ehud Arye LaniadoThe booming bear: the story of Russian diamond industry.ehudlaniado.com, Aug. 13, 5p.RussiaNews item - history
DM1509-0769
2015
Ehud Arye LaniadoIs the midstream working for a wage? A call for more profitable midstream for a stronger industry.ehudlaniado.com, Aug. 17, 5p.GlobalNews item - polishers
DM1509-0770
2015
Ehud Arye LaniadoKey changes offer bright future for diamond industry.info @ehudlaniado.com, Aug. 24, 3p.GlobalNews item - economics
DM1509-0771
2015
Ehud Arye LaniadoDiamond centers - Dubai profiled.ehudlaniado.com, Aug. 26, 4p.DubaiNews item - Dubai
DM1510-2034
2015
Ehud Arye LaniadoA call for change, a call for hope.ehudlaniado.com, Aug. 31, 4p.GlobalNews item - market
DM1510-2035
2015
Ehud Arye LaniadoHong Kong's rise to diamond fame.ehudlaniado.com, 4p.Hong KongNews item - Hong Kong
DM1510-2036
2015
Ehud Arye LaniadoThe awakening of diamonds in China ( jewellery)ehudlaniado.com, Sept. 9, 4p.ChinaNews item - markets
DM1510-2037
2015
Ehud Arye LaniadoStability in the diamond market.ehudlaniado.com, Sept. 21, 5p.GlobalNews item - markets
DM1510-2038
2015
Ehud Arye LaniadoDiamond mining in Namibia - past and present.ehudlaniado.com, Sept. 24, 3p.Africa, NamibiaNews item - history
DM1511-2139
2015
ehud Arye LaniadoThe diamonds's place in the consumer's heart.ehudlaniado.com, Oct. 5, 3p.GlobalNews item - history
DM1511-2140
2015
Ehud Arye LaniadoUnderstanding seasonality in diamond sales.ehudlaniado.com, Oct. 15, 8p.GlobalNews item - markets
DM1512-2243
2015
Ehud Arye Laniado$ 48 .4 million for 'blue Moon' diamond eclipses world auction record.ehudlaniado.com, Nov. 12, 2p.GlobalNews item - diamond notable
DM1512-2244
2015
Ehud Arye LaniadoRetail Economics: why consolidation could be helping the entire diamond retail industry.ehudlaniado.com, Nov. 25, 3p.GlobalNews item - prices
DS1505-0241
2015
Elazar, O., Kessel, R., Navon, O.Fluids and melts in equlibrium with carbonated hydrous eclogite system at 4-6 Gpa and 900-1200 C.Israel Geological Society, Abstracts 1p.TechnologyEclogite
DS1506-0264
2015
El-Desoky, H., Khalil, A.E., Salem, A.K.A.Ultramafic rocks in Gabal El-Rubshi, Central Eastern Desert, Egypt: petrography, mineral chemistry, and geochemistry constraints.Arabian Journal of Geosciences, Vol. 8, 5, pp.2607-2631.Africa, EgyptUltramafic rocks - general
DC1511-2380
2015
Element SixElement Six announced the use of its researchers at MQ Photonics to demonstrate a diamond laser 20 times more powerful than previous ones.Element Six, Sept. 23, 1/2p.TechnologyNews item - Element Six
DC1509-1481
2015
Elkedra Diamonds NL.Canadian master diamond cutter Mike Botha to craft the Esperanza diamond in Arkansas.Embee Diamonds, Aug. 27, 1/2p.United States, ArkansasNews item - Embee
DM1503-0772
2015
EMJ WompRio Tinto developing Diavik's A21 pipe.womp-int.com, Jan. 29, 1/3p.Canada, Northwest TerritoriesNews item - Rio Tinto
DC1508-1482
2015
EMU NLSale of Superkolong diamond interest final payment from El Nino Mining.EMU NL, July 17, 1/8p.AustraliaNews item - press release
DS1512-1916
2015
Evans, K.A., Powell, R.The effect of subduction on sulphur, carbon and redox budget of lithospheric mantle.Journal of Metamorphic Geology, Vol. 33, 6, pp. 649-670.MantleSubduction

Abstract: Subduction of hydrated lithospheric mantle introduces Hinline imageO, ferric iron, oxidized carbon and sulphur to the subduction zone system. The fate of these components is poorly known, but is intimately linked to the global geochemical cycles of iron, carbon and sulphur, the genesis of arc-related ore deposits, the temporal evolution of mantle redox state and subduction-related earthquakes and magmatism. thermocalc is used to provide first-order constraints on the effect of subduction zone metamorphism on metamorphic redistribution of iron, carbon, sulphur and water in ultramafic rocks via construction of P-T and T-X(O) pseudosections with open system calculation of the effect of fluid loss. The calculations replicate observed mineral assemblages in high-P to low-T ultramafic rocks at P-T conditions consistent with those suggested by other workers. The results are consistent with open system fluid loss without significant fluid infiltration. Water loss is complete by 850 inline imageC, the corresponding depth of fluid loss being consistent with that inferred for earthquakes in subducting slabs. Losses of carbon and sulphur are relatively minor, at around <5% and <1%, respectively, so it is envisaged that most carbon and sulphur subducted in ultramafic lithologies is transported to >5 GPa, below the depths of the source zone for arc volcanoes. Oxygen activity for rocks in closed systems that evolve with a fixed redox budget is calculated to change from ?FMQ -1 at 350 inline imageC to over ?FMQ +3 at 850 inline imageC. This result emphasizes the need to consider redox budget as well as oxygen activity when the results of experiments performed at fixed oxygen activity relative to some buffer are interpreted in the context of natural systems. In open systems, devolatilization is calculated to increase the redox budget and oxygen activity of the residue via loss of methane and Hinline imageS at the brucite-out and serpentine-out reactions respectively. No fluid-induced mechanism for oxidation of sub-arc mantle by transfer of redox budget from hydrated ultramafic lithologies to the overlying sub-arc mantle was identified, although further thermodynamic data on fluid species such as Sinline image are required to confirm this.
DM1510-2108
2015
Evans, N.Bit by bit sale for Ellendale. The West Australian, Sept. 3, 1p.AustraliaNews item - Kimberley Diamonds
DM1512-2245
2015
Evans, N.Diamond Daze - Ellendale Upbeat corporate forecasts, it transpires, were based on no more than an assumption that Tiffany would pay more for yellow diamonds.The Australian News , Nov. pp. 8-10. pdfAustraliaNews item - Kimberley Diamonds
DM1501-0475
2014
Even-Zohar, C.Another certificate movie: Dirty Dancing … using analogy to ethical grading and different labs.Diamond Intelligence Briefs ( Courtesy of Chaim), DIB 839, Nov. 25, pp. 8941-8945.TechnologyNews item - diamond certificates
DM1501-0476
2014
Even-Zohar, C.Analyzing Indian dreams of duty free jewelry exports to the United States.Diamond Intelligence Briefs ( Courtesy of Chaim), DIB 838, Nov. 19, pp. 8927-8930.India, United StatesNews item - GSP program
DM1501-0477
2014
Even-Zohar, C.Tyler Gillard: 'OECD has no plans to issue precious stones ( or diamonds) Due Diligence Guidelines at this time. Discusses The white paper initiative.Diamond Intelligence Briefs ( Courtesy of Chaim), DIB 837, Nov. 12, pp. 8913-17.GlobalNews item - OECD
DM1502-0774
2015
Even-Zohar, C.Analyzing Indian dreams of duty-free jewelry exports to the United States.Idex Magazine, No. 297, Jan. pp. 112-117.IndiaNews item - jewelry
DM1503-0775
2015
Even-Zohar, C.Economics 101: a course on added value.DIB , Vol. 30, 848, Jan. 28, pp. 9038-9042.GlobalNews item - statistics
DM1503-0776
2015
Even-Zohar, C.Diamond miracles from the Holy Land…. Offical diamond import and export statistics ( KP and Israel)…. Observations and concerns.DIB , Vol. 30, 845, Jan. 7, pp. 9008-9010.GlobalNews item - statistics
DM1503-0777
2015
Even-Zohar, C.False ABN-AMRO withdrawal scare in India.DIB , Vol. 30, 846, Jan. 15, pp. 9018-9020.IndiaNews item - banking, financing
DM1503-0778
2015
Even-Zohar, C.Taking one's banker to court. ABN-AMRODIB , Vol. 30, 847, Jan. 22, pp. 9029-9032.IndiaNews item - legal
DM1506-0779
2015
Even-Zohar, C.The year the industry lost confidence in its future.Diamond Intelligence Briefing Courtesy of Chaim), Vol. 30, 855, Apr. 27, 3p.GlobalNews item - supply chain
DM1507-0780
2015
Even-Zohar, C.ABN AMRO's Indian exit: Induslnd bank catapults into $ 1 billion exposure.Diamond Intelligence Briefing ( Courtesy of Chaim), Vol. 30, 854, Apr. 13, 8p.IndiaNews item - Induslnd
DM1507-0781
2015
Even-Zohar, C.Botswana beneficiation from a marketing agreement perspective: local rough supplies - a promise broken.Diamond Intelligence Briefing ( Courtesy of Chaim), Vol. 30, 856, May 11, 8p.Africa, BotswanaNews item - beneficiation
DM1509-0773
2015
Even-Zohar, C.Love and hate on the rough supply side. Diamond Intelligence Briefing, Vol. 30, no. 860, July 23, 8p.GlobalNews item - rough
DM1510-2039
2015
Even-Zohar, C.The emerging secrets of a bank destined to close. Antwerp Diamond Bank ( ADB)Diamond Intelligence Briefing ( Courtesy of Chaim), Vol. 30, no. 862, Sept. 11, 11p.Europe, BelgiumNews item - ADB legal
DM1511-2209
2015
Even-Zohar, C.Beneficiation from a marketing agreement perspective… factories, management and history.Idex Magazine, No. 306, pp. 38-62.Africa, BotswanaBeneficiation, production

Abstract: The President of Botswana, the Honorable Seretse Khama Ian Khama, has all the legitimate means to fix the plight of his country's ailing diamond-beneficiation sector, i.e., factory closings and the retrenchment of some 700 workers during the past few months. Only one thing is needed to turn the situation around: to muster the political will and courage to do so. This may sound like an impossible challenge given today's diamond market and economic realities - but it can be done. In fact, it must be done, according some stakeholders in Botswana. This isn't for someone from the outside to say. The president of Botswana heads an independent sovereign government, and it is up to him to set the policy priorities in his country.
DM1512-2246
2015
Even-Zohar, C.Violating the 11th commandment: thou shalt not discount… Supplier and Client stood eyeball-to-eyeball in price standoff - De Beers blinked first.Diamond Intellgence Briefing (Courtesy of Chaim), Vol. 30, no. 864, Oct. 26, 9p.GlobalNews item - De Beers
DM1512-2247
2015
Even-Zohar, C.The riddle of De Beers and $ 5 billion of "invisible" production… Diamond Intellgence Briefing (Courtesy of Chaim), Vol. 30, no. 863, Oct. 1, 9p.GlobalNews item - production figures
DS1506-0266
2015
Even-Zohar, C.Taxing the Antwerp diamond industry into prosperity.Idex Magazine, No. 301, pp. 111-117.EuropeEconomics
DS1507-0311
2015
Even-Zohar, C.Temporary color enhancement: a potential game changer for industry and grading labs.Diamond Intelligence Briefing ( Courtesy of Chaim), Vol. 30, no. 857, May 28, 8p.TechnologyDiamond - colours
DS1508-0354
2015
Even-Zohar, C.Temporary colour enhancement …. Treatment, story so far, timing, legal and commercial problems of dishonesty.Idex Magazine, No. 303, July pp. 36-62.TechnologyDiamond color enhancement
DS1504-0195
2015
Ewing, I.Ice, ice baby A frigid winter paves the way for Gahcho Kue.Canadian Institute of Mining and Metallurgy, March-April 2p.Canada, Northwest TerritoriesDeposit - Gahcho Kue
DS1510-1767
2015
Eyike, A., Ebbing, J.Lithospheric structure of the West and Central African Rift system from regional three dimensional gravity modelling. South African Journal of Geology, Vol, 118, no. 3, pp. 285-298.Africa, East AfricaGeophysics - gravity

Abstract: A three-dimensional interpretation of the central part of the West and Central African Rift System (WCARS) is presented using the Earth Gravity Model 2008 (EGM2008). The 3-D model presented here provides new insights into the regional lithospheric structure of the central sector of the WCARS. The 3-D model reveals a possible crustal thickness and density distribution beneath the rift system, and the depth extent of magmatic activity in the Benue Trough is revealed for the first time. Because of asthenospheric uplift, the crust under the Benue Trough is thinned. The zone of crustal thinning (<30 km) coincides with the trace of an intrusion beneath the trough, and the maximum of which is attained in the Yola Basin. The Adamawa and Kapsiki Plateaus, on the other hand, show by far the largest crustal thickness in the region (34 to 36 km). The inferred zone of intrusion coincides with the maximum gravity anomaly of the rift zone. The great depth (ca. 14 km) to the top of the intrusion along the rift may explain the absence of magmatism in the Benue Trough compared to the Cameroon Volcanic Line (CVL) or the East African Rift System (EARS). The relatively small nature of the intrusion leads to the conclusion that small-scale asthenospheric upwelling might be responsible for the thinning of the crust and subsequent rifting of the Benue Trough.
DS1501-0007
2014
Fahrenkamp-Uppenbrink, J.What drives Earth's thermodynamic engine?Science, Vol. 346, 6214, pp. 1184-1185.MantleAthenosphere, magmatism
DS1512-1917
2015
Fajber, R., Simandl, G.J., Luck, P., Neetz, M.Biogeochemical methods to explore for carbonatites and related mineral deposits: an orientation survey, Blue River area, British Columbia, Canada.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 241-244.Canada, British ColumbiaCarbonatite

Abstract: Carbonatites host economic deposits of niobium (Nb), rare earth elements (REE), phosphate, baddeleyite (natural zirconia), vermiculite, and fl uorspar, and historically, supplied copper, uranium, carbonate (for cement industries) and sodalite (Pell, 1994 and Simandl, this volume). The Upper Fir carbonatite is in southeastern British Columbia, approximately 200 km north of Kamloops (Fig. 1). It is one ofmany known carbonatite occurrences in the British Columbia alkaline province, which follows the Rocky Mountain Trench and extends from the southeastern tip of British Columbia to its northern boundaries with the Yukon and Northwest Territories (Pell, 1994). The Upper Fir is a strongly deformed carbonatite with an indicated mineral resource of 48.4 million tonnes at 197 ppm of Ta2O5 and 1,610 ppm of Nb2O5, and an inferred resource of 5.4 million tonnes at 191 ppm of Ta2O5 and 1760 ppm of Nb2O5 (Kulla et al. 2013). The Nb, Ta, and vermiculite mineralization is described by Simandl et al. (2002, 2010), Chong, et al, (2012), and Chudy (2014). In this document we present the results of an orientation survey designed to determine the biogechemical signature of a typical carbonatite in the Canadian Cordillera. This survey suggests that needles and twigs of White Spruce (Picea glauca) and Subalpine Fir (Abies lasio carpa) are suitable sampling media to explore for carbonatites and carbonatite-related rare earth elements (REE), niobium (Nb), and tantalum (Ta) deposits.
DS1511-1834
2015
Fedortchouk, Y.Diamond resorption features as a new method of examining conditions of kimberlite emplacement.Contributions to Mineralogy and Petrology, Vol. 170, 19p.GlobalDiamond morphology - etch pits

Abstract: The study develops a new approach utilizing parameters of trigonal etch pits on diamond crystals to infer the conditions of diamond residence in kimberlite magma. Diamond crystals from dissolution experiments conducted at 1 GPa and 1150-1350 °C in the presence of H2O-rich or CO2-rich fluid were studied with atomic force microscopy (AFM). The AFM data of resorbed diamond surfaces show that much deeper surface relief was produced in CO2 fluid. It also clearly distinguishes the profiles of the trigonal etch pits forming regular flat-bottomed trigons in H2O fluid, and round- or pointed-bottomed trigons in CO2 fluid. The relationship between the diameter and the depth of the trigonal pits is found to be another important indicator of the fluid composition. Dissolution in H2O fluid develops trigons with constant diameter and variable depth where the diameter increases with temperature. Trigons developed in CO2 fluid have a large range of diameters showing a strong positive correlation with the depth. The developed criteria applied to the natural diamond crystals from three Ekati Mine kimberlites indicate significant variation in CO2-H2O ratio and temperature of their magmatic fluid. This conclusion based on diamond resorption agrees with the mineralogy of microphenocrysts and groundmass of the studied kimberlites offering new method to study crystallization conditions of kimberlite magma. Keywords
DS1512-1918
2015
Feng, J., Tappert, M.C., Rivard, B.A., Fulop, A., Rogge, D., Tappert, R.Acquiring crustal dilution data and kimberlite compositional information from drill core using SWIR hyperspectral imagery from the Tango extension kimberlite.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 39.Canada, Northwest TerritoriesDeposit - Tango

Abstract: Short-wave infrared (SWIR, 1.90-2.36 µm) hyperspectral imagery collected from 171 meters of drill core from the diamondiferous Tango Extension kimberlite using a high spatial resolution imaging system (pixel size: 1.43 x 1.43 µm) was analyzed to create compositional maps that show the distribution of different crustal (dilution) components and different kimberlite types along the drill core. Three types of crustal dilution components were identified in the compositional maps: carbonate, a carbonate-mudstone mixture, and mudstone. Five spectrally distinct types of kimberlite were identified, which differ mainly in their level of hydration and the amount of crustal micro-dilution they contain. Accompanying the compositional maps are depth profiles that provide quantitative abundance information for each compositional component (dilution and kimberlite). These profiles show the abundance of macro-dilution relative to kimberlite and the spatial distribution of the different kimberlite types. Using depth profiles, compositional boundaries along the length of the drill core were identified and compared to the unit boundaries from the visual lithological log. The boundaries identified using the hyperspectral imagery correlate well with the boundaries recorded during visual logging. This study demonstrates that hyperspectral imagery is well suited to the task of mapping the distribution of spectrally distinct kimberlite types, and quantifying kimberlite micro- and macro-dilution by crustal rocks.
DS1501-0008
2014
Fernandes, A.F., Karfunkel, J., Hoover, D.B., Sgarbi, P.B.De Al., Sgarbo, G.N.C., Oliveira, G.D., Gomes, J.C.de S.P., Kambrock, K.The basal conglomerate of the Capacete Formation ( Mata da Corda Group) and its relation to diamond distributions in Coromandel, Minas Gerais State, Brazil.Brazil Journal of Geology, Vol. 44, 1, pp. 91-103.South America, BrazilCoromandel district

Abstract: The diamond bearing district of Coromandel is located in the northwestern part of Minas Gerais, within the Alto Paranaíba Arch, famous for the discovery of most of Brazil's large diamonds above 100 ct. Detailed mapping, aimed at characterizing the Mata da Corda Group of Upper Cretaceous age of Coromandel, has been carried out. This Group was divided into the Patos Formation, composed of kimberlitic and kamafugitic rocks, and the Capacete Formation, presented by conglomerates, pyroclastic rocks, arenite and tuffs. Exposures of the latter Formation have been studied in detail at the small abandoned mine called Canastrel, as well as in the headwater of Santo Antônio do Bonito River. The results have been compared to studies of the kimberlite bodies in the nearby Douradinho River. Kimberlite indicator minerals from these localities show the same compositional trend. Moreover, in the basal conglomerate of the Garimpo Canastrel two diamonds diamonds have been recovered and described. The Garimpo Wilson, situated in the headwater of the river Santo Antônio do Bonito in paleo-alluvium, is composed of material exclusively derived from the erosion of the Capacete Formation and Precambrian (sterile) Canastra quartzites and schists. These detailed investigations suggest that the basal conglomerates of the Capacete Formation represent the main source rock of the alluvial diamond deposits in the Coromandel region.
DS1505-0250
2015
Ferracutti, G.R., Gargiulo, M.F., Ganuza, M.L., Bjerg, E.A., Castro, S.M.Determination of the spinel group end-members based on electron microprobe analyses.Mineralogy and Petrology, Vol. 109, 2, pp. 153-160.TechnologyGeochronology
DS1511-1835
2012
Ferreira, J.Motete dyke project … preliminary diamond grade and tonnage model for the Motete dyke.MSA Group for Paragon Diamonds, April, 17p. Available pdfAfrica, LesothoMicrodiamonds - responses

Abstract: The Motete Dyke is a diamondiferous kimberlite situated in the mountains of Lesotho. Total liberation diamond recovery methods were used to analyse representative samples from localities along the 1 500 m outcrop length of the dyke for grade modeling purposes. The microdiamond grade and stone density is remarkably consistent throughout the exposed area of the dyke. A grade of some 60 cpht at +1.18 mm and 90 cpht at +0.85 mm is estimated for the dyke at surface. In order to extend the estimate to deeper levels it will be necessary to drill into the dyke to obtain more sampling material for total liberation analysis. Initial tonnage calculations indicate that the dyke contains an estimated 525 000 carats at +0.85 mm with an additional 50 000 carats in every additional 10 m depth below 2450 m elevation, assuming an average dyke width of 1.44 m and density of 2.57 tons/m3. Bulk sampling of the dyke is recommended to recover a parcel of diamonds for valuation and to confirm the diamond size frequency and content model.
DS1506-0267
2015
Ferrero, S., Wunder, B., Walczak, K., O'Brien, P.J., Ziemann, M.A.Preserved near ultrahigh-pressure melt from continental crust subducted to mantle depths.Geology, Vol. 43, 5, pp. 447-450.MantleBohemian
DC1501-1483
2014
Firestone Diamonds plc.Liqhobong mine development project update.Firestone Diamonds plc., Dec. 2, 3p.Africa, LesothoNews item - press release
DC1504-1484
2015
Firestone Diamonds plc.Highlights from results six months to 31 December. Liqobong, BK-11, financesFirestone Diamonds plc., Mar. 12, 14p.Africa, Lesotho, BotswanaNews item - press release
DC1506-1485
2015
Firestone Diamonds plc.Proposed standby debt facility and restructuring of the existing mezzanine facility. LiqhobongFirestone Diamonds plc., Apr. 24, 3p.Africa, LesothoNews item - press release
DC1507-1486
2015
Firestone Diamonds plc.Liqhobong mine development project update.Firestone Diamonds plc., June 23, 4p.Africa, LesothoNews item - press release
DC1508-1487
2015
Firestone Diamonds plc.Sale of Botswana operations. BK11 mine to Tango.Firestone Diamonds plc., July 9, 2p.Africa, BotswanaNews item - press release
DC1511-2381
2015
Firestone Diamonds plc.Update on the sale of the Botswana operations to Tango Mining Limited … requested an extension to the timetable.Firestone Diamonds plc., Oct. 2, 1p.Africa, BotswanaNews item - press release
DC1511-2382
2015
Firestone Diamonds plc.Final results for year ended 30 June 2015. Liqhobong on budget.. Capital investment US $ 82.9 million … restructuring of Botswana assets.Firestone Diamonds plc., Oct. 6, 3p.Africa, LesothoNews item - press release
DC1511-2383
2015
Firestone Diamonds plc.Update on the sale of the Botswana operations and extension to Tango to April 8, 2016.Firestone Diamonds plc., Oct. 13, 1p.Africa, BotswanaNews item - press release
DS1504-0196
2012
Firsching, M., Muhlbauer, J., Nachtrab, F., Jobst, A.Basis material decomposition a quantitative X-ray imaging method and its application in industrial sorting.International Symposium on Digital Industrial Radiology and computed Tomography, Poster 13, 5p.TechnologyDiamond recovery
DS1504-0197
2012
Firsching, M., Muhlbauer, J., Nachtrab, F., Uhlmann, N.Detection of enclosed diamonds using dual energy X-ray imaging.18th. World Conference on Nondestructive Testing held Durban SA, 7p.TechnologyDiamond recovery
DS1502-0056
2015
Firsov, A., Ashchepkov, I., Rikhvanov, L.The alkali basaltic and picritic magmatism in Minusa and Kusnetsk basin - geochemical study.Economic Geology Research Institute 2015, Vol. 17,, # 2797, 1p. AbstractRussiaPicrite
DC1512-2432
2015
Five Star Diamonds LimitedListing in H1 2016 The company plans to develop a 3.5 hectare kimberlite pipe at its Catalano project, Goias district.ProactiveInvestors @sut8.co.uk, Nov. 27, 1p.South America, BrazilNews item - Five Star Diamonds
DM1510-2040
2015
ForbesCullinan Heritage diamond 507.55 Carat type 11a has been cut by Chow Tai Fook …Forbes Magazine, Sept. 4p.Africa, South AfricaNews item - diamond notable
DS1501-0009
2014
Fournier, D., Heagy, L., Corcoran, N., Cowan, D., Devriese, S.G.R., Bild-Enkin, D., Davis, K., Kang, S., Marchant, D., McMillan, M.S., Mitchell, M., Rosenkjar, G., Yang, D., Oldenburg, D.W.Multi-EM systems inversion - towards a common conductivity model for Tli Kwi Cho complex.SEG Annual Meeting Denver, 5p. Extended abstractCanada, Northwest TerritoriesDeposit - Tli Kwi Cho, geophysics

Abstract: The magnetic and electromagnetic responses from airborne systems at Tli Kwi Cho, a kimberlite complex in the Northwest Territories, Canada, have received considerable attention over the last two decades but a complete understanding of the causative physical properties is not yet at hand. Our analysis is distributed among three posters. In the first we find a 3D magnetic susceptibility model for the area; in the second we find a 3D conductivity model; and in the third we find a 3D chargeability model that can explain the negative transient responses measured over the kimberlite pipes. In this second paper we focus upon the task of finding a conductivity model that is compatible with three airborne data sets flown between 1992 and 2004: one frequency-domain data set (DIGHEM) and two time-domain systems (AeroTEM and VTEM). The goal is to obtain a 3D model from which geologic questions can be answered, but even more importantly, to provide a background conductivity needed to complete the 3D IP inversion of airborne EM data. We begin by modifying our pre-existing 1D frequency and time domain inversion codes to produce models that have more lateral continuity. The results are useful in their own right but we have also found that 1D analysis is often very effective in bringing to light erroneous data, assisting in estimating noise floors, and providing some starting information for developing a background model for the 3D EM inversion. Here we show some results from our Laterally Constrained Inversion (LCI) framework. The recovered conductivity models seem to agree on the general location of the kimberlite pipes but disagree on the geometry and conductivity values at depth. The complete 3D inversions in time and frequency, needed to resolved these issues, are currently in progress.
DS1509-0396
2015
France, L., Chazot, G., Kornprobst, J., Dallai, L., Vannucci, R., Gregoire, M., Bertrand, H., Boivin, P.Mantle refertilization and magmatism in old orogenic regions: the role of late-orogenic pyroxenites.Lithos, Vol. 232, pp. 49-75.Africa, Morocco, Cameroon, Jordan, Europe, FranceXenoliths

Abstract: Pyroxenites and garnet pyroxenites are mantle heterogeneities characterized by a lower solidus temperature than the enclosing peridotites; it follows that they are preferentially involved during magma genesis. Constraining their origin, composition, and the interactions they underwent during their subsequent evolution is therefore essential to discuss the sources of magmatism in a given area. Pyroxenites could represent either recycling of crustal rocks in mantle domains or mantle originated rocks (formed either by olivine consuming melt-rock reactions or by crystal fractionation). Petrological and geochemical (major and trace elements, Sr-Nd and O isotopes) features of xenoliths from various occurrences (French Massif-Central, Jordan, Morocco and Cameroon) show that these samples represent cumulates crystallized during melt percolation at mantle conditions. They formed in mantle domains at pressures of 1-2 GPa during post-collisional magmatism (possibly Hercynian for the French Massif-Central, and Panafrican for Morocco, Jordan and Cameroon). The thermal re-equilibration of lithospheric domains, typical of the late orogenic exhumation stages, is also recorded by the samples. Most of the samples display a metasomatic overprint that may be either inherited or likely linked to the recent volcanic activity that occurred in the investigated regions. The crystallization of pyroxenites during late orogenic events has implications for the subsequent evolution of the mantle domains. The presence of large amounts of mantle pyroxenites in old orogenic regions indeed imparts peculiar physical and chemical characteristics to these domains. Among others, the global solidus temperature of the whole lithospheric domain will be lowered; in turn, this implies that old orogenic regions are refertilized zones where magmatic activity would be enhanced.
DS1505-0253
2015
Fraser InstituteFraser Institute annual survey for 2014. Mining jurisdictions listed.Fraser Institute, 97p. PdfGlobalLegal
DS1504-0198
2015
Frezzotti, M.L., Ferrando, S.The chemical behaviour of fluids released during deep subduction based on fluid inclusions.American Mineralogist, Vol. 100, pp. 352-377.MantleSubduction
DS1512-1919
2015
Friis, H.Primary and secondary mineralogy of the Ilimaussaq alkaline complex, south Greenland.Symposium on critical and strategic materials, British Columbia Geological Survey Paper 2015-3, held Nov. 13-14, pp. 83-90.Europe, GreenlandAlkalic

Abstract: The Ilímaussaq alkaline complex is among the largest known alkaline complexes in the world and has been studied since the early 19th century, when Giesecke explored Greenland for minerals. More than 230 different mineral species occur in the complex. Ilímaussaq is the type locality for 34 minerals, including 15 that have not been reported elsewhere. Some of these are rock-forming minerals and thus, although unique to Ilímaussaq, may not be considered rare. Among the minerals fi rst described from Ilímaussaq are two important sources for critical materials: steenstrupine- (Ce) and eudialyte (Table 1). Steenstrupine-(Ce) is the main target mineral for the Kvanefjeld multi-element project in the northern part of Ilímaussaq, whereas eudialyte is targeted at the Tanbreez project in the southern part known as Kringlerne (Fig. 1). The fi rst detailed mapping and petrological studies of the complex were published by Ussing (1912), who also defi ned the term ‘agpaitic’ for rocks where the molar ratio (Na+K)/ Al is greater than or equal to 1.2. Since then, the distinction between agpaitic and miaskitic has changed from being based on just rock chemistry to being based more on mineral paragenesis. Sørensen (1997) defi ned agpaitic as peralkaline rocks in which High Field Strength Elements (HFSE; e.g., Zr and Ti) are hosted in complex minerals such as eudialyte and rinkite. Rocks with high alkalinity, where HFSE are hosted in minerals such as zircon, are considered miaskitic. Khomyakov (1995) further developed the agpaitic classifi cation by introducing the term hyperagpaitic for the most evolved syenites. Hyperagpaitic rocks are characterised by containing water soluble minerals (e.g., natrosilite and natrophosphate) and complex phosphosilicates (e.g., steenstrupine-(Ce) and vuonnemite; Khomyakov, 1995). The Ilímaussaq complex is one of several alkaline complexes formed during Mesoproterozoic rifting in the southwestern part of Greenland, which collectively is called the Gardar province (Upton, 2013). With an age of ~1.6 Ga, Ilímaussaq is the youngest major intrusion of the Gardar province (Waight et al., 2002; Krumrei et al., 2006).
DS1506-0268
2015
Frizon de Lamotte, D., Fourdan, B., Leleu, S., Leparmentier, F., de Clarens, P.Style of rifting and the stages of Pangea break up.Tectonics, Vol. 34, 5, pp. 1009-1029.Global, RussiaPangea
DS1501-0010
2003
FulgroHeliFALCONtm gravity gradiometer Gahcho Kue kimberlite pipes. ( Kennady Lake JV)fugro.com, 2p.Canada, Northwest TerritoriesDeposit - Gahcho Kue geophysics
DS1505-0233
2015
Furlani, S., Ninfo, A.Is the present the key to the future?Earth Science Reviews, Vol. 142, pp. 38-46.GlobalGeomorphology
DS1501-0011
2015
Fusciardi, L.De Beers Canada - technology and innovation across the diamond value chain.PDAC 2015, 1/4p. AbstractCanadaDe Beers
DS1503-0144
2015
Gaillou, E., Post, J.E., Byne, K.S., Butler, J.E.Study of the Blue Moon diamond. ( from Cullinan)Gems & Gemology, Vol. 50, 4, winter 2014, 9p.Africa, South AfricaDiamonds notable

Abstract: The Blue Moon diamond, discovered in January 2014 at the historic Cullinan mine in South Africa, is of significance from both trade and scientific perspectives. The 29.62 ct rough yielded a 12.03 ct Fancy Vivid blue, Internally Flawless gem. The authors were provided the opportunity to study this rare diamond at the Smithsonian Institution before it went on exhibit at the Natural History Museum of Los Angeles County. Infrared spectroscopy revealed that the amount of uncompensated boron in the diamond was 0.26 ± 0.04 ppm, consistent with measurements of several large type IIb blue diamonds previously studied. After exposure to short-wave ultraviolet light, the Blue Moon displayed orange-red phosphorescence that remained visible for up to 20 seconds. This observation was surprising, as orange-red phosphorescence is typically associated with diamonds of Indian origin, such as the Hope and the Wittelsbach-Graff. Time-resolved phosphorescence spectra exhibited peaks at 660 and 500 nm, typical for natural type II blue diamonds. As with most natural diamonds, the Blue Moon showed strain-induced birefringence.
DS1504-0199
2015
Gannoun, A., Burton, K.W., Barfod, D.N., Schiano, P., Vlastelic, I., Halliday, A.N.Resolving mantle and magmatic processes in basalts from the Cameroon volcanic line using the Re-Os isotopic system.Lithos, Vol. 224-5, pp. 1-12.Africa, CameroonAlkaline rocks, basalts
DS1508-0355
2015
Garanin, V.K.The Fersman mineralogical museum in the 21st century: past, present and future,Mineral @fmmm.ru, Vol. 18, 3, pp. 24-41.RussiaHistory - Fersman
DS1506-0269
2014
Garanin, V.K., Leybov, M.B.Diamonds: a sketch portrait (History of discovery of Russian deposits and their genesis).Mineralogical Almanac, Vol. 19, 1, pp. 30-47.RussiaHistory
DC1504-1488
2015
Gem Diamonds LimitedFull year results for the period ending 31 December 2014.Gem Diamonds Limited, Mar. 17, 3p.AfricaNews item - Gem Diamonds
DC1504-1489
2015
Gem Diamonds LimitedFull year 2014 results… Letseng, Ghaghoo.Gem Diamonds Limited, Mar. 17, 3p.Africa, Lesotho, BotswanaNews item - press release
DC1506-1490
2015
Gem Diamonds LimitedSales and operational update … Letseng, Ghaghoo.Gem Diamonds Limited, May 21, 6p.Africa, Lesotho, BotswanaNews item - press release
DC1509-1491
2015
Gem Diamonds LimitedTrading update and projects Letseng and Ghaghoo performances.Gem Diamonds Limited, July 30, 3p.Africa, Lesotho, BotswanaNews item - press release
DC1510-2347
2015
Gem Diamonds LimitedSale of 357 ct. Letseng diamond $ 19.3 m Gem Diamonds Limited, Sept. 14, 1p.Africa, LesothoNews item - press release
DS1507-0312
2015
Gernon, T.M., Spence, S., Trueman, C.N., Taylor, R.N., Rohling, E., Hatter, S.J., Harding, I.C.Emplacement of Cabezo Maria lamproite volcano (Miocene) SE Spain.Bulletin of Volcanology, Vol. 77, 6, pp. 52-Europe, SpainLamproite
DS1510-1768
2015
Gerya, I.T.Tectonic overpressure and underpressure in lithospheric tectonics and metamorphism.Journal of Metamorphic Geology, Vol. 33, 8, pp. 785-800.MantleTectonics

Abstract: The lithostatic pressure concept is most commonly applied on a geological scale for lithospheric processes and related evolution of metamorphic rock complexes. Here, various aspects of non-lithostatic overpressure and underpressure phenomena in lithospheric tectonics and metamorphism are reviewed on the basis of recently published literature. The main conclusion from this short review is that these phenomena certainly exist in nature on all time and space scales including geological ones. They are, in particular, responsible for some geological processes, which are otherwise difficult to explain, such as downward water suction into the interior of subducting slabs. Magnitudes of overpressure and underpressure are strongly variable and may potentially reach up to ±100% of the lithostatic pressure and up to a GPa-level. These magnitudes depend mainly on the rheology of deforming rocks and on the nature of related tectonic process. Rheological heterogeneity of deforming rock units, which is common in nature, has a tendency to enhance overpressure and underpressures. Large overpressure can typically be expected in rheologically strong (dry) bending rock units, in particular in the mantle lithosphere. However, rheological weakness of rocks and small local deviatoric stresses do not guarantee the absence of large overpressures in these rocks. Therefore, the influence of significant tectonic overpressure and/or underpressure cannot be excluded for any metamorphic complex a priori but should be instead tested by exploring realistic thermomechanical models for envisaged tectono-metamorphic scenarios. Many lithospheric rocks subjected to large overpressures and underpressures cannot be studied as they do not exhume to the surface. Some controversy exists concerning overpressure magnitudes for the ultrahigh-pressure (UHP) rocks and several conflicting hypotheses are proposed, which need to be thoroughly tested in the future. In this respect, the Alpine region may offer a unique opportunity for the testing of geological-scale overpressures in (U)HP rocks by combining structural-geological and petrological data with realistic lithospheric-scale numerical modelling.
DS1502-0057
2014
Gifford, J.N., Mueller, P.A., Foster, D.A, Mogk, D.W.Precambrian crustal evolution in the Great Falls Tectonic Zone: insights from xenoliths from the Montana Alkali province.Journal of Geology, Vol. 122, Sept. pp. 531-548.United States, MontanaAlkalic
DS1507-0313
2015
Gilio, M., Clos, F., Van Roermund, H.L.M.The Frimingen garnet peridotite ( central Swedish Caledonides). A good example of the characteristic PTt path of a cold mantle wedge garnet peridotite.Lithos, Vol. 230, pp. 1-16.Europe, SwedenPeridotite
DS1505-0235
2015
Giuliani, G.,Pivin, M., Fallick, A.E., Ohnenstetter, D., Song, Y., Demaiffe, D.Geochemical and oxygen isotope signatures of mantle corundum megacrysts from the Mbuji-Mayi kimberlite, Democratic Republic of Congo and the Changle alkali basalt, China.Comptes Rendus Geoscience, Vol. 347, 1, pp. 24-34.Africa, Democratic Republic of Congo, ChinaDeposit - Mbuji-Mayi
DS1512-1920
2015
Gokhale, M., Madhura, Somani, R., RakeshFullerenes: chemistry and its applications.Mini-Reviews in Organic Chemistry, Vol. 12, 4, pp. 355-366.TechnologyFullerenes

Abstract: Fullerenes being allotropes of carbon, have been considered as new class of molecules. Unlike diamond and graphite, this is made up of hollow carbon cage structure. The idea of spheroidal cage structures of C60 arose from construction of geodesic domes made by renowned architect Buckminster Fuller. Although fullerenes have low solubility in physiological media they finds promising biological applications. The photo, electrochemical and physical properties of C60 and other fullerene derivatives finds applications in medical fields. The ability of fullerenes to fit inside the hydrophobic cavity of HIV proteases makes them potential inhibitor for substrates to catalytic active site of enzyme. It possesses radical scavenging and antioxidant property. At the same time, when it exposed to light it can form singlet oxygen in high quantum yields which with direct electron transfer from excited state of fullerenes and DNA bases finally results in cleavage of DNA. The fullerenes are also used as a carrier for gene and drug delivery system. The associated low toxicity of fullerenes is sufficient to attract the researchers for investigation of these interesting molecules.
DC1502-1492
2015
Golden Saint Resources Ltd.Golden Saint samples diamond recoveries at Baja.Golden Saint Resources Ltd., Jan. 20, 1p.Africa, Sierra LeoneNews item - press release
DC1504-1493
2015
Golden Saint Resources Ltd.Golden Saint Resources has recovered a total of 233 carats of diamonds during the first stage of its bulk sampling programme at Baja.Golden Saint Resources Ltd., Mar. 10, 2p.Africa, Sierra LeoneNews item - press release
DC1505-1494
2015
Golden Saint Resources Ltd.Quarterly update .. Moa project, Baja project and Tongo project brief summaries.Golden Saint Resoures Ltd., Mar. 27, 1p.Africa, Sierra LeoneNews item - press release
DC1505-1495
2015
Golden Saint Resources Ltd.GSR boss says new licences mean full steam ahead in Sierra Leone.Golden Saint Resoures Ltd., Apr. 14, 1p.Africa, Sierra LeoneNews item - press release
DC1506-1496
2015
Golden Saint Resources Ltd.Operational update: bulk sampling at Tongo, 9.475 carat diamond.Golden Saint Resources Ltd., Apr. 27, 1p.Africa, Sierra LeoneNews item - press release
DC1506-1497
2015
Golden Saint Resources Ltd.Highlights … Baja,Moa.Golden Saint Resources Ltd., May 20, 40p.Africa, Sierra LeoneNews item - press release
DC1506-1498
2015
Golden Saint Resources Ltd.Operation update - two stones 9.65 and 0.775 from Tongo Golden Saint Resources Ltd., May 28, 1p.Africa, Sierra LeoneNews item - press release
DC1507-1499
2015
Golden Saint Resources Ltd.Operational update ongoing sampling exercise in Tongo.Golden Saint Resources Ltd., May 28,1p.Africa, Sierra LeoneNews item - press release
DC1508-1500
2015
Golden Saint Resources Ltd.Appointment of technical and exploration consultant…. Rock Forage Consulting Services. John WardGolden Saint Resources Ltd., June 30, 1p.Africa, Sierra LeoneNews item - press release
DC1508-1501
2015
Golden Saint Resources Ltd.Operational update to the market: diamonds found 2.25, 2.62, 4.41, 3.12, 89 carat under .05 caratGolden Saint Resources Ltd., July 3, 1p.Africa, Sierra LeoneNews item - press release
DC1510-2348
2015
Golden Saint Resources Ltd.Interim results .. Bulk sampling Tongo and Baja; Zimmi area artisanal.Golden Saint Resources Ltd., Sept. 21, 2p.Africa, Sierra LeoneNews item - press release
DC1511-2384
2015
Golden Saint Resources Ltd.Geological report on alluval and kimberlite of Baja, Tongo and Moa from Rock Forage consultants.Golden Saint Resources Ltd., Oct. 1, 2p.Africa, Sierra LeoneNews item - press release
DC1512-2433
2015
Golden Saint Resources Ltd.Placing, operational updates and board changes. Tongo bulk samplingGolden Saint Resources Ltd., Nov. 24, 1p.Africa, Sierra LeoneNews item - press release
DM1512-2248
2015
Goldie, R.Alrosa responds to weak Q3 markets.SalmanResearch @salmanpartners.com, Nov. 25, 1/4p.RussiaNews item - Alrosa
DS1504-0200
2015
Goldie, R.Diamonds .. Nominal US dollar price for rough diamonds graphThe 2015 Commodity Price Book, p. 31 ( I pg graph)GlobalPrice index
DS1506-0270
2015
Gomes de Moraes Rocha, L., Bittencourt Pires, A.C., Chatck Carmelo, A., Oksum, E.Curie surface of the alkaline provinces of Goias (GAP) and Alto Paranaiba ( APAP), central Brazil.Journal of Volcanology and Geothermal Research, Vol. 297, pp. 28-38.South America, BrazilKimberlites, Lineaments
DS1512-1921
2015
Gorbachev, N.S., Kostyuk, A.V., Shapovalov, Yu.B.Experimental study of the basalt-carbonate-H2O system at 4 Gpa and 1100-1300C: origin of carbonatitic and high-K silicate magmas.Doklady Earth Sciences, Vol. 464, 2, pp. 1018-1022.TechnologyCarbonatite
DS1501-0012
2014
Grad, M., Tiira, T., Olsson, S., Komminaho, K.Seismic lithosphere asthenosphere boundary beneath the Baltic Shield.GFF, Vol. 136, 4, pp. 581-598.Europe, Finland, Sweden, NorwayGeophysics - seismic

Abstract: The problem of the existence of the asthenosphere for old Precambrian cratons is still discussed. In order to study the seismic lithosphere-asthenosphere boundary (LAB) beneath the Baltic Shield, we used records of nine local earthquakes with magnitudes ranging from 2.7 to 5.9. To model the LAB, original data were corrected for topography and Moho depth using a reference model with a 46-km-thick crust. For two northern events at Spitsbergen and Novaya Zemlya, we observe a low-velocity layer, 60-70-km-thick asthenosphere, and the LAB beneath Barents Sea was found at depth of c. 200 km. Sections for other events show continuous first arrivals of P-waves with no evidence for "shadow zone" in the whole range of registration, which could either be interpreted as the absence of the asthenosphere beneath the central part of the Baltic Shield, or that the LAB in this area occurs deeper (>200 km). The relatively thin low-velocity layer found beneath southern Sweden, 15 km below the Moho, could be interpreted as small-scale lithospheric heterogeneities, rather than asthenosphere. Differentiation of the lower lithosphere velocities beneath the Baltic Shield could be interpreted as regional heterogeneity or as anisotropy of the Baltic Shield lithosphere, with high velocities approximately in the east-west direction, and slow velocities approximately in the south-north direction.
DS1502-0058
2015
Graedel, T.E., Nassar, N.T.The criticality of metals: a perspective for geologists.In: Ore deposits of an evolving Earth, Geological Society of London,, Special Publication no. 393, pp. 291-302.GlobalEconomics
DS1503-0145
2015
Green, D.H.Experimental petrology of peridotites, including effects of water and carbon on melting in the Earth's upper mantle.Physics and Chemistry of Minerals, Vol. 42, 2, pp. 95-122.MantlePeridotite

Abstract: For over 50 years, the use of high-pressure piston/cylinder apparatus combined with an increasing diversity of microbeam analytical techniques has enabled the study of mantle peridotite compositions and of magmas derived by melting in the upper mantle. The experimental studies have been guided by the petrology and geochemistry of peridotites from diverse settings and by the remarkable range of mantle-derived magma types. Recent experimental study using FTIR spectroscopy to monitor water content of minerals has shown that fertile lherzolite (MORB-source upper mantle) at ~1,000 °C can store ~200 ppm H2O in defect sites in nominally anhydrous minerals (olivine, pyroxenes, garnet and spinel). Water in excess of 200 ppm stabilizes amphibole (pargasite) at P < 3 GPa up to the lherzolite solidus. However, at P > 3 GPa, water in excess of 200 ppm appears as an aqueous vapour phase and this depresses the temperature of the upper mantle solidus. Provided the uppermost mantle (lithosphere) has H2O < 4,000 ppm, the mantle solidus has a distinctive P, T shape. The temperature of the vapour-undersaturated or dehydration solidus is approximately constant at 1,100 °C at pressures up to ~3 GPa and then decreases sharply to ~1,010 °C. The strongly negative dT/dP of the vapour-undersaturated solidus of fertile lherzolite from 2.8 to 3 GPa provides the basis for understanding the lithosphere/asthenosphere boundary. Through upward migration of near-solidus hydrous silicate melt, the asthenosphere becomes geochemically zoned with the ‘enriched’ intraplate basalt source (>500 ppm H2O) overlying the ‘depleted’ MORB source (~200 ppm H2O). From the study of primitive MOR picrites, the modern mantle potential temperature for MORB petrogenesis is ~1,430 °C. The intersection of the 1,430 °C adiabat with the vapour-saturated lherzolite solidus at ~230 km suggests that upwelling beneath mid-ocean ridges begins around this depth. In intraplate volcanism, diapiric upwelling begins from shallower depths and lower temperatures within the asthenosphere and the upwelling lherzolite is enriched in water, carbonate and incompatible elements. Magmas including olivine melilitites, olivine nephelinites, basanites, alkali picrites and tholeiitic picrites are consequences of increasing melt fraction and decreasing pressure at melt segregation. Major element, trace element and isotopic characteristics of island chain or ‘hot-spot’ magmas show that they sample geochemically distinct components in the upper mantle, differing from MORB sources. There is no evidence for higher-temperature ‘hot-spot’ magmas, relative to primitive MORB, but there is evidence for higher water, CO2 and incompatible element contents. The distinctive geochemical signatures of ‘hot-spot’ magmas and their ‘fixed’ position and long-lived activity relative to plate movement are attributed to melt components derived from melting at interfaces between old, oxidised subducted slabs (suspended beneath or within the deeper asthenosphere) and ambient, reduced mantle. In convergent margin volcanism, the inverted temperature gradients inferred for the mantle wedge above the subducting lithosphere introduce further complexity which can be explored by overlaying the phase relations of appropriate mantle and crustal lithologies. Water and carbonate derived from the subducted slab play significant roles, magmas are relatively oxidised, and distinctive primary magmas such as boninites, adakites and island arc ankaramites provide evidence for fluxing of melting in refractory harzburgite to lherzolite by slab-derived hydrous adakitic melt and by wedge-derived carbonatite.
DS1505-0246
2015
Griffin, W.L., Gain, S.E.M., Toledo, V., O'Reilly, S.Y., Jacob, D., Pearson, N.J.Corundum, moissanite and super reducing conditions in the upper mantle beneath the lower ( southern) Galilee ( Israel).Israel Geological Society, 1p.posterEurope, IsraelMineralogy
DC1504-1502
2015
Grizzly Discoveries Inc.Brief note on overview .. Buffalo Head Hills and Birch Mountains.Grizzley Discoveries Inc., Mar. 18, 1p.Canada, Saskatchewan, AlbertaNews item - press release
DC1506-1503
2015
Grizzly Discoveries Inc.Renewed interest in diamonds.. Buffalo Hills project.Grizzly Discoveries Inc., May 6, 1p.Canada, AlbertaNews item - press release
DS1502-0060
2015
Grocholski, B.A lower mantle water cycle component.Science, Vol. 347, 6220, Jan. 23, pp. 385-386.MantleWater
DS1509-0397
2015
Grocholski, B.Unlocking Earth's ancient magnetic past.Science, Vol. 349, 6247, pp. 490-492.MantlePaleomagnetism

Abstract: The magnetic field protects Earth's surface from deadly cosmic radiation and provides clues about the planet's interior. Tarduno et al. found that some of the oldest minerals on Earth, Jack Hills zircons, preserved a record of a magnetic field over 4 billion years ago (see the Perspective by Aubert). Earth's magnetic field appears to have been fully operational a mere few hundred million years after the planet formed. This suggests an early start for plate tectonics and an ancient cosmic radiation shield that was important for habitability.
DS1510-1769
2015
Grocholski, B.Broadening the source for hotspots.Science, Vol. 349, 6255, Sept. 25, pp. 1501-1502.MantleHotspots
DS1511-1836
2015
Grocholski, B.Coupled constraints on core formation.Science, Vol. 350, 6258, Oct. 16, pp. 289-290.MantleChemistry
DM1505-0782
2015
Grynberg, R.Diamond cutting industry in Botswana.Allafrica.com, Apr. 22, 2p.Africa, BotswanaNews item - opinion comments
DS1511-1837
2015
Gu, Y.J., Shen, L.Noise correlation tomography of southwest western Canada sedimentary basin. Geophysical Journal International, Vol. 202, pp. 142-162.Canada, AlbertaGeophysics - seismics

Abstract: We analyse continuous recordings from 23 broadband seismic stations near Alberta, the southwestern sector of the Western Canada Sedimentary Basin. Noise correlation tomo-graphy based on vertical-component seismograms reveals below-average shear velocities at shallow and middle crustal depths in central Alberta, spanning across Proterozoic accreted terranes and Archean microcontinents. This observation likely results from extensive plate convergence and crustal melting during the Proterozoic eon. The overall correlation between the crustal velocities and presumed basement domains is lower than expected, however. In the lower crust, the main pattern of shear velocities is relatively concordant with the reported domain boundaries and key Precambrian structures appear to be intact. The shear velocities beneath the Loverna Block, the largest constituent of the Hearne craton, are 10?per?cent higher than the regional average. This prominent northeast striking seismic anomaly is moderately correlated with the regional heat flow and potentially represents the remnant core of the Archean Hearne province. The associated high velocities extend into the western part of the Medicine Hat Block, a possible Archean microcontinent with a debatable origin, and contribute to a strong east-west structural gradient in the lower crust. The presence and the continuity of this anomalous structure imply extensive communications among the various basement domains in southern Alberta during the assembly of the North American continent.
DS1510-1770
2015
Gudmundsson, A.Collapse-driven large eruptions.Journal of Volcanology and Geothermal Research, Vol 304, pp. 1-10.MantleMagmatism

Abstract: For a typical poroelastic shallow crustal magma chamber, about 0.1% of the mafic magma and about 4% of the felsic magma are erupted and/or injected during magma-chamber rupture. Magma chambers with volumes of the order of several tens to several hundred cubic kilometres, as are common, are thus sufficiently large to supply magma to small or moderate eruptions. For large eruptions, however, a much higher percentage of the magma volume must be squeezed out of the chamber. For an ordinary poroelastic chamber, the excess pressure in the chamber falls exponentially during the eruption. For a large eruption to be possible, however, the excess pressure must be essentially maintained until the very end of the eruption. Here I show that caldera collapse can maintain the excess pressure through forced magma-chamber volume reduction, in which case a resulting large eruption would be the consequence (not the cause) of the collapse. I also show that ring-fault dip partly controls the size and intensity (volumetric flow or effusion rate) of the eruption. If the ring-fault dips inward (a normal fault), the displacement is ‘stable’, the volumetric flow rate (intensity) remains essentially constant during the collapse, and the magma chamber remains active following the collapse. By contrast, if the ring-fault dips outward (a reverse fault), the displacement is ‘unstable’, the volumetric flow rate normally increases dramatically during the collapse, and the magma chamber may be entirely destroyed during the collapse.
DS1506-0271
2015
Gueydan, F., Pitra, P., Afiri, A., Poujol, M., Essaifi, A., Paquette, J-L.Oligo-Miocene thinning of the Beni Bousera peridotites and their Variscan crustal host rocks, Internal Rif, Morocco.Tectonics, Vol. 34, pp.1244-1268.Africa, MoroccoPeridotite
DS1512-1922
2015
Guha, A., Kumar, K.V., Ravi, S., Dhananjaya Rao, E.N.Reflectance spectroscopy of kimberlites - in parts of Dharwar Craton, India.Arabian Journal of Geosciences, Vol. 8, no. 11, pp. 9373-9388.IndiaDeposit - Narayanpet

Abstract: In the present study, an attempt was made to analyse the reflectance spectra of kimberlites to evaluate its potential as key in remote sensing based spatial mapping. The spectral profiles of kimberlite samples were collected within the visible-near infrared-shortwave infrared (VNIR-SWIR) electromagnetic domain. In this regard, we analysed the reflectance spectra of three kimberlite pipes (having variable mineralogy) of Narayanpet kimberlite field (NKF) based on the comparative analysis of spectral features of kimberlite samples with the spectral features of their dominant constituent minerals. The relative abundances of each of the constituent minerals were confirmed using semiquantitative mineralogical data from X-ray diffraction analysis. This was supplemented with petrographical data as reference. We found that the absorption features imprinted in the reflectance spectra of kimberlites were mineralogically sensitive. These spectral features were imprinted by spectral features of serpentine, olivine, and calcite depending on the relative dominance of these minerals in kimberlites. With regard to understand the spectral behaviour of weathered residue of kimberlite for targeting buried kimberlite, we also attempted a comparative analysis of spectral profiles of in-situ soil developed above the pipes with the spectra of respective kimberlites in NKF area. While comparing aforementioned spectra, it was observed that the spectral signatures of NKF kimberlites were broadly translated to the in-situ soil. Further, we compared the spectral profiles of selected NKF kimberlites with the spectra of three distinct kimberlite pipes of Wajrakarur kimberlite field (WKF) characterised with similar mineralogy with respect to the selected NKF pipes. Relative dominance of constituent minerals (i.e., serpentine, olivine, calcite, etc.) in these pipes was taken as reference to identify the mineralogical similarity of the pipes of both the field. It was observed that the spectral profiles of NKF and WKF kimberlites were highly correlated with regard to wavelength of diagnostic absorption features. Finally, we also made an attempt to understand the effect of spectral mixing, in spectral separation of kimberlites and associated granite-granodiorite gneiss (i.e., Dharwar Gneiss). It was seen that the spectral contrast of kimberlite and gneiss was dependent on the relative size of the pipe with respect to pixel or ground sampling diameter of spectral data acquisition. Study confirmed the diagnostic nature of reflectance spectra of pipes along with their mineralogical sensitiveness and spatial integrity. It also highlighted how spectral mixing can influence the spectral feature based remote detection of kimberlites.
DS1511-1838
2007
Guidolin, M., La Ferrara, E.Diamonds are forever, war is not: is conflict bad for private firms?The American Economic Review, Vol. 97, 5, pp. 1978-1993.GlobalEconomics

Abstract: This paper studies the relationship between civil war and the value of firms in a poor, resource abundant country using microeconomic data for Angola. We focus on diamond mining firms and conduct an event study on the sudden end of the conflict, marked by the death of the rebel movement leader in 2002. We find that the stock market perceived this event as “bad news” rather than "good news" for companies holding concessions in Angola, as their abnormal returns declined by 4 percentage points. The event had no effect on a control portfolio of otherwise similar diamond mining companies. This finding is corroborated by other events and by the adoption of alternative methodologies. We interpret our findings in the light of conflict-generated entry barriers, government bargaining power and transparency in the licensing process.
DS1503-0146
2015
Guzmics, T., Zajacz, Z., Mitchell, R.H., Szabo, C., Walle, M.The role of liquid-liquid immiscibility and crystal fractionation in the genesis of carbonatite magmas: insights from Kerimasi melt inclusions.Contributions to Mineralogy and Petrology, Vol. 169, 18p.Africa, TanzaniaCarbonatite

Abstract: We have reconstructed the compositional evolution of the silicate and carbonate melt, and various crystalline phases in the subvolcanic reservoir of Kerimasi Volcano in the East African Rift. Trace element concentrations of silicate and carbonate melt inclusions trapped in nepheline, apatite and magnetite from plutonic afrikandite (clinopyroxene-nepheline-perovskite-magnetite-melilite rock) and calciocarbonatite (calcite-apatite-magnetite-perovskite-monticellite-phlogopite rock) show that liquid immiscibility occurred during the generation of carbonatite magmas from a CO2-rich melilite-nephelinite magma formed at relatively high temperatures (1,100 °C). This carbonatite magma is notably more calcic and less alkaline than that occurring at Oldoinyo Lengai. The CaO-rich (32-41 wt%) nature and alkali-"poor" (at least 7-10 wt% Na2O + K2O) nature of these high-temperature (>1,000 °C) carbonate melts result from strong partitioning of Ca (relative to Mg, Fe and Mn) in the immiscible carbonate and the CaO-rich nature (12-17 wt%) of its silicate parent (e.g., melilite-nephelinite). Evolution of the Kerimasi carbonate magma can result in the formation of natrocarbonatite melts with similar composition to those of Oldoinyo Lengai, but with pronounced depletion in REE and HFSE elements. We suggest that this compositional difference results from the different initial parental magmas, e.g., melilite-nephelinite at Kerimasi and a nephelinite at Oldoinyo Lengai. The difference in parental magma composition led to a significant difference in the fractionating mineral phase assemblage and the element partitioning systematics upon silicate-carbonate melt immiscibility. LA-ICP-MS analysis of coeval silicate and carbonate melt inclusions provides an opportunity to infer carbonate melt/silicate melt partition coefficients for a wide range of elements. These data show that Li, Na, Pb, Ca, Sr, Ba, B, all REE (except Sc), U, V, Nb, Ta, P, Mo, W and S are partitioned into the carbonate melt, whereas Mg, Mn, Fe, Co, Cu, Zn, Al, Sc, Ti, Hf and Zr are partitioned into the silicate melt. Potassium and Rb show no preferential partitioning. Kerimasi melt inclusions show that the immiscible calcic carbonate melt is strongly enriched in Sr, Ba, Pb, LREE, P, W, Mo and S relative to other trace elements. Comparison of our data with experimental results indicates that preferential partitioning of oxidized sulfur (as SO4 2-), Ca and P (as PO4 3-) into the carbonate melt may promote the partitioning of Nb, Ta, Pb and all REE, excluding Sc, into this phase. Therefore, it is suggested that P and S enrichment in calcic carbonate magmas promotes the genesis of REE-rich carbonatites by liquid immiscibility. Our study shows that changes in the partition coefficients of elements between minerals and the coexisting melts along the liquid line of descent are rather significant at Kerimasi. This is why, in addition to the REE, Nb, Ta and Zr are also enriched in Kerimasi calciocarbonatites. We consider significant amounts of apatite and perovskite precipitated from melilite-nephelinite-derived carbonate melt as igneous minerals can have high LREE, Nb and Zr contents relative to other carbonatite minerals.
DS1501-0013
2015
Gysi, A.P., Willams-Jones, A.E.The thermodynamic properties of Bastnasite-(Ce) and parisite-(Ce).Chemical Geology, Vol. 392, pp. 87-101.REE
DS1507-0314
2015
Hacker, B.R., Kelemen, P.B., Behn, M.D.Continental lower crust.Annual Review of Earth and Planetary Sciences, Vol. 43, pp. 167-205.MantleSubduction
DS1512-1923
2015
Haiblen, A.M., Ward, B.C., Normandeau, P.X., Prowse, N.D.Glacial history and landform genesis in the Lac de Gras area and implications for kimberlite drift prospecting.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 43.Canada, Northwest TerritoriesGeomorphology

Abstract: During the last glaciation, bedrock was eroded, transported and deposited by the Laurentide Ice Sheet across much of Canada. The complex ice and meltwater processes that resulted in sediment deposition are not completely understood. In the central Slave Craton, Northwest Territories, glacial sediments overly many diamond-bearing kimberlites. Diamond deposits in the Lac de Gras area were discovered in the early 1990s by drift prospecting. To better interpret drift prospecting datasets a more thorough understanding of the detailed glacial history of the area is required. We spent six weeks in the Lac de Gras area in summer 2015. Field mapping was complimented by a number of other techniques to elucidate the glacial history of the area. Enigmatic landforms were examined in detail and pits were dug to examine their sedimentology. Samples of matrix material were collected to compare grain size distribution between different sediment types. Pebble counts were done to consider sediment provenance. We also collected ground-penetrating radar profiles to look for stratified sediments within enigmatic mounds. High-resolution orthophotos and a one metre LiDAR digital elevation model of the area, obtained by Dominion Diamond Ekati Corporation, have also been used to investigate landform genesis and the glacial history of the area. In the Lac de Gras area many meltwater corridors can be identified in the high-resolution imagery. These corridors are typically 300-1500 m wide and form dendritic networks. Between the corridors, sandy till of varying thickness overlies bedrock. Within corridors, glaciofluvial landforms and scoured bedrock are common. Also associated with corridors are many mounds of enigmatic origin. These mounds commonly occur in groups and are typically 20-100 m wide and rise 5-15 m above the surrounding area. They are usually composed of an unstratified to poorly-stratified sandy diamicton containing no clay and minor silt. Matrix grain size distribution and pebble lithology results from some mounds are similar to those of nearby regional till. However, patches of well-stratified sediments, exhibiting laminated silts as well as climbing ripples in sand, do exist on parts of some mounds. GPR data suggests that these patches are discontinuous, and that the majority of mounds are composed largely of sandy diamicton. Variation in the sedimentology of the mounds does not appear to be related to variations in mound morphology. It is likely that the majority of the glaciofluvial sediments in the Lac de Gras area were deposited during the final stages of ice retreat across the area when meltwater volumes were high. We suggest that the corridors were formed by subglacial meltwater flow. This is because glaciofluvial deposition almost exclusively occurs within corridors, very little till is found within corridors and the corridors have an undulating elevation profile in the direction of ice flow. Water must have played a role in the deposition of the well-stratified patches of sediment found on some mounds, however, the mounds may not be solely the product of subglacial meltwater flow. A thorough understanding of sediment transport and depositional processes is critical if kimberlite indicator mineral data is to be accurately interpreted.
DS1509-0398
2015
Hainschwang, T., Notari, F.The first undisclosed colourless CVD synthetic diamond discovered in a parcel of natural melee sized diamonds.The Journal of Gemmology, Vol. 334, 6, pp. 518-522.TechnologySynthetics

Abstract: During the March 2015 Diamond Show in Basel, Switzerland, a parcel of 6,000 melee-sized colourless diamonds was analysed using the GGTL Diamond Fluorescence Imaging (DFI) Laser+ fluorescence imaging and spectroscopy system. From the entire parcel, one sample stood out clearly with unusual fluorescence colours and distribution, combined with a photoluminescence spectrum that clearly indicated it was a synthetic diamond grown by chemical vapour deposition (CVD).
DS1503-0147
2014
Hainschwang, T., Notari, F., Vadaszi, E.The Rhodesian Star: an exceptional asteriated diamond.The Journal of Gemmology, Vol. 34, 4, pp. 306-315.Africa, ZimbabweDiamonds notable
DS1503-0148
2014
Hainschwang,T.Diamants de type 1b: relations entre les proprietes physiques et gemmologiques des diamants contenant de l'Azote Isole.Thesis, University of Nantes, France., In French * reference onlyTechnologyNitrogen
DS1512-1924
2015
Hallis, L.J., Huss, G.R., Nagashima, K., Taylor, G.J., Halldorsson, S.A.Evidence of primordial water in Earth's deep mantle.Science, Vol. 350, 6252 Nov. 13, pp. 795-797.MantleWater

Abstract: The hydrogen-isotope [deuterium/hydrogen (D/H)] ratio of Earth can be used to constrain the origin of its water. However, the most accessible reservoir, Earth’s oceans, may no longer represent the original (primordial) D/H ratio, owing to changes caused by water cycling between the surface and the interior. Thus, a reservoir completely isolated from surface processes is required to define Earth’s original D/H signature. Here we present data for Baffin Island and Icelandic lavas, which suggest that the deep mantle has a low D/H ratio (dD more negative than -218 per mil). Such strongly negative values indicate the existence of a component within Earth’s interior that inherited its D/H ratio directly from the protosolar nebula.
DS1506-0272
2015
Hamling, I.J., Wallace, L.M.Silent triggering: aseismic crustal faulting induced by a subduction slow slip event.Earth and Planetary Science Letters, Vol. 421, pp. 13-19.MantleSubduction
DS1510-1771
2015
Hammouda, T., Keshav, S.Melting in the mantle in the presence of carbon: review of experiments and discussion on the origin of carbonatites.Chemical Geology, in press availableMantleCarbonatite

Abstract: Carbon emission at volcanic centers requires a constant balance between output (mostly by volcanism, either at plate boundaries or intraplate) and input (mostly at trench settings) of carbon from and to the Earth's mantle. The form of carbon that resides in the mantle is controlled by depth (pressure) and oxygen fugacity, the latter in turn depending on the depth and the concentration of iron in the mantle. In the shallow, lithospheric mantle, carbon is likely to be present in the oxidized form of CO2 (except under cratons where carbon is reduced to graphite or diamond). Below approximately 90 km, in the asthenosphere, the oxidized form of carbon is carbonate, either mineral or melt, depending on the thermal regime. At depths greater than approximately 150 km, the asthenospheric mantle is too reducing for carbon to stay in its oxidized form and only diamond is present, unless there is sufficient hydrogen to form reduced C-H fluids. Hence, the region located in the depth range of 90 to 150 km deep is where carbonatitic melts can most likely be produced and impregnate the surrounding mantle through metasomatism. The upper bound of this region is called the carbonate ledge. This limit prevents carbonate (either solid or molten) from ascending because of degassing and CO2 liberation. The lower bound is a redox front where redox melting (that is, melting caused by oxidation) may take place in an ascending portion of carbon-containing mantle. Carbonatite eruptions and presence of carbonate mineral inclusions in deep-seated diamonds provide evidence that these boundaries can be trespassed in some cases. An analysis of the experimental data that has bearing on silicate melting in the presence of carbon further shows that the carbonate ledge is a melting curve with a negative or flat Clapeyron (dP/dT) slope. In the carbonated ultrabasic (peridotite) systems, the carbonate ledge is located between ~ 2-3 GPa. The ledge divides the pressure-temperature space into a region of low-pressure silicate melt production, and a high-pressure region where carbonatites can be produced. Carbonatitic melts in equilibrium with mantle peridotite have compositions close to dolomitic (approximately equal amounts of Ca and Mg) with a general trend of becoming markedly more magnesian with increasing pressure. Calcic carbonatites may be stable at pressures < 2 GPa if clinopyroxene is absent. At mantle transition zone pressure range, there seems to be a melting temperature decrease (negative fusion slope), which may be caused by the stabilization of majoritic garnet. The carbonated basic (broadly eclogitic) system is more complex than the peridotitic one, because of the strong control of bulk silicate composition on melting temperatures, and hence, on melt composition. In carbonated eclogite systems, we propose that the effect of bulk composition upon all observed features can perhaps be related to silica super-saturation, or lack thereof. In some cases, high calcium (> 80 mol% CaCO3) melts can be produced, making the melting of carbonated eclogites an appealing scenario for the genesis of calcio-carbonatites in the Earth's mantle. Comparison with modeled pressure-temperature paths of subducted oceanic lithosphere shows that fusion of carbonated eclogite at depths shallower than 200 km should be expected for hot (Cascadian-type) subduction thermal regimes. On the other hand, in the case of cooler thermal regimes (Honshu-type, for instance), subducted carbonates may be stable to greater depths in Earth at trench settings, depending on the bulk composition of the system. Furthermore, high-pressure experiments show evidence of a continuum among carbonatitic, kimberlitic, melilititic, and basaltic liquids, for increasing melting degree of carbonated peridotite. This continuum has not been documented in the case of fusion of carbonated eclogite. It may be present, however, when certain sediments are fused, although the silicate melts are granitic to rhyodacitic instead of being kimberlitic in composition. Additional high-pressure work on phase relations in the simple binary system CaCO3-MgCO3 and specific focus on oxide solubility in the vapor phase have the potential to further clarify phase relations on complex silicate-carbonate systems at mantle conditions.
DS1510-1772
2015
Hand, E.Mantle plumes seen rising from Earth's core.Science, Vol. 349, 6252, pp. 1032-1033.MantlePlume

Abstract: Mantle plumes, tubes of hot rock rising from Earth's core, have come into focus, ending a more than 40-year-long debate. The result comes from a sophisticated MRI-like tomographic model that used 273 large earthquakes to illuminate the interior of Earth. It revealed as many as 28 plumes, many of them underneath known volcanic hot spots at Earth's surface. The plumes are fatter than expected, which means that they carry more heat away from Earth's core, an indication that plumes are important for cooling the planet. The model also shows that the plumes bend at a depth of 1000 kilometers, which could indicate an undiscovered mineral phase transition in the lower mantle that makes it less stiff.
DS1512-1925
2015
Hand, E.How buried water makes diamonds and oils.Science, Vol. 350, 6261, pp. 613-614.TechnologyDiamond genesis

Abstract: Under high pressures, water can react with surrounding rock to make diamonds and oil. These are just two consequences of a new picture of water's versatile chemistry in the mantle. The Deep Earth Water model is showing that, under extreme pressures down to 200 kilometers, water can dissolve many ions and host unexpected new reactions. It is replacing a geochemical framework, published in 1981, which made predictions for water-rock interactions, but only down to 15 kilometers. The idea that oil can be made from water and rock in the mantle is controversial, because it has long been assumed that oil arises through the compaction and burial of organic matter.
DS1511-1839
2015
Hansen, V.L.Impact origin of Archean cratons.Lithosphere, Vol. 7, pp. 563-578,MantleImpacts

Abstract: Earth was a completely different planet more than 2.5 billion years ago. Little is known about this critical time when cratonic continental seeds formed; life emerged; and precious mineral resources concentrated. Our knowledge is limited because plate tectonic processes destroyed most of this early record. In contrast, Earth's sister, Venus -- similar in size, density, bulk composition, and distance from the Sun -- never developed plate tectonics. Venus also lacks a water cycle. Like siblings, Venus and Earth were most similar in their youth; however, Venus preserves a more complete geological record of its infancy, including both exogenic and endogenic features. Applying clues from Venus, Vicky L. Hansen proposes a new hypothesis for the formation of Earth's cratons. Large bolides pierced early thin lithosphere causing massive partial melting in the ductile mantle; melt escaped upward, forming cratonic crust; meanwhile strong, dry, buoyant melt residue formed cratonic roots, serving as unique buoyant life preservers during future plate-tectonic recycling.
DS1511-1840
2015
Harada, Y., Hishinuma, R., Terashima, C., Uetsuka, H., Nakata, K., Kondo, T., Yuasa, M., Fujishima, A.Rapid growth of diamond and its morphology by in-liquid plasma CVD.Diamond and Related Materials, in press available, 16p.TechnologySynthetics

Abstract: Diamond synthesis and its morphology by in-liquid plasma chemical vapor deposition (CVD) method are investigated in this study. Diamond films were grown on Si substrates from mixed alcohol solution. Very high growth rate of 170 µm/h was achieved by this method. Microcrystalline and nanocrystalline diamond films were formed in different conditions. In the case of microcrystalline film, the shapes of diamond grains depend on the location in the film. All morphological differences in this study can be explained by the same mechanism of conventional gas phase CVD method. It means diamond morphology by in-liquid plasma CVD method can be controlled by process parameters as well as gas phase CVD method.
DS1512-1926
2015
Hardman, M.F., Stachel, T., Pearson, D.G., Kinakin, Y.B., Bellinger, J.Improving the utility of eclogitic garnet in diamond exploration - examples from Lac de Gras and worldwide localities.43rd Annual Yellowknife Geoscience Forum Abstracts, abstract p. 47.Canada, Northwest TerritoriesGarnet chemistry

Abstract: In diamond exploration, the use of compositional data to identify diamond-related peridotitic xenocrysts has long been a widely used and powerful tool. In contrast, the application of similar methods to eclogitic garnet chemistry remains a challenge. The inability to unequivocally classify certain “eclogitic” garnet compositions as either mantle- or crust-derived implies that a high abundance of lower-crustal garnets will increase diamond-exploration expenditures by introducing a number of “false positives.” Revising existing classification schemes (e.g., Schulze, 2003) to reduce the abundance of “false positives” may, however, increase the number of “false negatives” through the misclassification of mantle-derived garnets as crustal. This study presents new geochemical and petrographical data for garnet and clinopyroxene from 724 kimberlite-hosted, crust- and mantle-derived xenoliths from localities worldwide, with a focus on samples whose lithology is constrained petrographically, rather than single mineral grains from concentrate. Mantle samples are primarily eclogitic and pyroxenitic, as constrained by mineral assemblage and garnet and clinopyroxene mineral chemistry, while crustal samples are dominantly plagioclase-bearing garnet-granulites. For those localities where an established geothermal gradient is available from literature resources, garnet-clinopyroxene pairs are employed in the estimation of pressure-temperature conditions of equilibration through the iterative coupling of the Krogh (1988) geothermometer and the relevant geothermal gradient. Our preliminary results suggest that closure temperatures for Fe-Mg exchange exceed the temperatures of residence of many lower-crustal samples, as geotherm-based calculated pressures of equilibration exceed the apparent stability of plagioclase (see Green and Ringwood, 1972). Comparison of equilibration pressures with sodium contents in garnet for mantle-derived samples (the diamond-facies criterion of Gurney, 1984) shows a positive correlation at localities for which an adequate range of pressures is observed (e.g., the Diavik mine). Other populations, such as mantle eclogitic garnets from Roberts Victor, plot at a much more restricted range of pressures and hence fail to demonstrate this correlation; instead, these samples may reflect the influence of a broader range of bulk-compositions, providing varying amounts of sodium to their constituent garnets. The results presented here demonstrate clearly that garnets from mantle- and crust-derived samples show significant overlap in geochemical character, for example in garnet Ca# vs. Mg# space (discrimination diagram of Schulze, 2003), where approximately 66% of our crust-derived garnet analyses plot in the “mantle” field. This percentage varies among locations. A selection of particularly high-Mg#, low-Ca# garnets derived from crustal, plagioclase-bearing lithologies in this study highlights the potential for crust-mantle confusion, as these garnets have Mg# in-excess of many mantle-derived eclogitic/pyroxenitic garnets. As a consequence, Fe-Mg-Ca-based classifications alone cannot reliably discriminate mantle and crustal garnets. The next step in this project will be to obtain trace element data for the entire sample suite. This will allow us to test the Li-geobarometer of Hanrahan et al. (2009) for eclogites and to search for trace element signatures that can be used as robust indicators of a diamond-facies origin of eclogitic garnets. Trace element data will also be employed in the refinement of the crust/mantle division discussed above.
DS1507-0315
2015
Harlow, G.E., Tsujimori, T., Sorensen, SS.Jadeites and plate tectonics.Annual Review of Earth and Planetary Sciences, Vol. 43, pp. 105-138.MantleJadeites
DS1511-1841
2015
Harris, J.R., Grunsky, E., Behnia, P., Corrigan, D.Data and knowledge-driven mineral prospectivity maps for Canada's north. (**note for Au )Ore Geology Reviews, Vol. 71, pp. 788-803.Canada, Nunavut, Melville PeninsulaGIS. IAS

Abstract: Data- and knowledge-driven techniques are used to produce regional Au prospectivity maps of a portion of Melville Peninsula, Northern Canada using geophysical and geochemical data. These basic datasets typically exist for large portions of Canada's North and are suitable for a "greenfields" exploration programme. The data-driven method involves the use of the Random Forest (RF) supervised classifier, a relatively new technique that has recently been applied to mineral potential modelling while the knowledge-driven technique makes use of weighted-index overlay, commonly used in GIS spatial modelling studies. We use the location of known Au occurrences to train the RF classifier and calculate the signature of Au occurrences as a group from non-occurrences using the basic geoscience dataset. The RF classification outperformed the knowledge-based model with respect to prediction of the known Au occurrences. The geochemical data in general were more predictive of the known Au occurrences than the geophysical data. A data-driven approach such as RF for the production of regional Au prospectivity maps is recommended provided that a sufficient number of training areas (known Au occurrences) exist.
DS1508-0356
2015
Harvey, J., Konig, S., Luguet, A.The effects of melt depletion and metasomatism on highly siderophile and strongly chalcophile elements: S-Se-Te-Re-PGE systematics of peridotite xenoliths from Kilbourne Hole, New Mexico.Geochimica et Cosmochimica Acta, Vol. 166, pp. 210-233.United States, New Mexico, Colorado PlateauPeridotite, xenoliths
DS1508-0357
2015
Hassan, R., Flament, N., Gurnis, M., Bower, D.J., Muller, D.Provenance of plumes in global convection models.Geochemistry, Geophysics, Geosystems: G3, Vol. 16, 5m pp. 1465-1489.AfricaConvection
DS1511-1842
2015
Hazen, R.M., Hystad, G., Downs, R.T., Golden, J.J., Pires, A.J., Grew, E.S.Earth's missing minerals.American Mineralogist, Vol. 100, pp. 2344-2347.TechnologyMineralogy

Abstract: Recent studies of mineral diversity and distribution lead to the prediction of >1563 mineral species on Earth today that have yet to be described-approximately one fourth of the 6394 estimated total mineralogical diversity. The distribution of these "missing" minerals is not uniform with respect to their essential chemical elements. Of 15 geochemically diverse elements (Al, B, C, Cr, Cu, Mg, Na, Ni, P, S, Si, Ta, Te, U, and V), we predict that approximately 25% of the minerals of Al, B, C, Cr, P, Si, and Ta remain to be described - a percentage similar to that predicted for all minerals. Almost 35% of the minerals of Na are predicted to be undiscovered, a situation resulting from more than 50% of Na minerals being white, poorly crystallized, and/or water soluble, and thus easily overlooked. In contrast, we predict that fewer than 20% of the minerals of Cu, Mg, Ni, S, Te, U, and V remain to be discovered. In addition to the economic value of most of these elements, their minerals tend to be brightly colored and/or well crystallized, and thus likely to draw attention and interest. These disparities in percentages of undiscovered minerals reflect not only natural processes, but also sociological factors in the search, discovery, and description of mineral species.
DS1502-0061
2015
He, L.Thermal regime of the North China craton: implications for craton destruction.Earth Science Reviews, Vol. 140, pp. 14-26.ChinaGeothermometry
DS1508-0358
2015
He, X-F., Santosh, M., Zhang, Z-M., Tsunogae, T., Chetty, T.R.K., Ram Moham, M., AnbazhaganShonkinites from Salem, southern India: implications for Cryogenian alkaline magmatism in rift related setting.Journal of Asian Earth Sciences, in press availableIndiaShonkinites
DS1504-0201
2015
Heaman, L.M., Pell, J., Grutter, H.S., Creaser, R.A.U-Pb geochronology and Sr/Nd isotope compositions of groundmass perovskite from the newly discovered Jurassic Chidliak kimberlite field, Baffin Island, Canada.Earth and Planetary Science Letters, Vol. 415, April pp. 183-189.Canada, Nunavut, Baffin IslandDeposit - Chidliak
DS1506-0273
2015
Herzog, F.A.The potential of a portable EDXRF spectrometer for gemmology. ( not specific to diamond)The Journal of Gemmology, Vol. 34, 5, pp. 404-418.TechnologySpectroscopy
DS1501-0014
2015
Hetman, C.Canadian diamonds: past, present and future.PDAC 2015, 1p. AbstractCanadaHistory
DS1503-0149
2015
Hill, P.J.A., Kopylova, M., Russell, J.K.Mineralogical controls on garnet composition in the cratonic mantle.Contributions to Mineralogy and Petrology, Vol. 169, 20p.MantleGarnet mineralogy
DS1512-1927
2015
Hiyate, A.Botswana beckons. Prolific diamond nation attracts explorers.Diamonds in Canada Magazine, Northern Miner, Nov. pp. 14-17.Africa, BotswanaOverview of companies
DS1502-0062
2014
Hoag, H.Earth's deep crust could support widespread life.Nature, Dec. 23, 1p.MantleMicrobial ecosystems
DC1511-2385
2015
Honey Badger Exploration Inc.Honey Badger Exploration receives TSX-V approval for LG diamonds project.Honey Badger Exploration Inc., Oct. 22, 1p.Canada, Quebec, James Bay LowlandsNews item - press release
DC1512-2434
2015
Honey Badger Exploration Inc.Honey Badger exploration identifies priority targets at its LG diamonds project.Honey Badger Exploration Inc., Nov. 19, 2p.Canada, QuebecNews item - press release
DS1509-0399
2015
Hongsresawat, S., Panning, M.P., Russo, R.M., Foster, D.A., Monteiller, V., Chevrot, S.USArray shear wave splitting shows seismic anisotropy from both lithosphere and asthenosphere.Geology, Vol. 43, 8, pp. 667-670.United StatesSeismic -anisotropy

Abstract: North America provides an important test for assessing the coupling of large continents with heterogeneous Archean- to Cenozoic-aged lithospheric provinces to the mantle flow. We use the unprecedented spatial coverage of the USArray seismic network to obtain an extensive and consistent data set of shear wave splitting intensity measurements at 1436 stations. Overall, the measurements are consistent with simple shear deformation in the asthenosphere due to viscous coupling to the overriding lithosphere. The fast directions agree with the absolute plate motion direction with a mean difference of 2° with 27° standard deviation. There are, however, deviations from this simple pattern, including a band along the Rocky Mountain front, indicative of flow complication due to gradients in lithospheric thickness, and variations in amplitude through the central United States, which can be explained through varying contributions of lithospheric anisotropy. Thus, seismic anisotropy may be sourced in both the asthenosphere and lithosphere, and variations in splitting intensity are due to lithospheric anisotropy developed during deformation over long time scales.
DS1504-0202
2015
Howarth, G.H., Sobolev, N.V., Pernet-Fisher, J.F., Ketcham, R.A., Maisano, J.A., Pokhilenko, L.N., Taylor, D.3-D X-ray tomography of diamondiferous mantle eclogite xenoliths, Siberia: a review.Journal of Asian Earth Sciences, Vol. 101, 1, pp. 39-67.RussiaDeposit - Udachnaya
DS1508-0359
2015
Howell, D., Fisher, D., Piazolo, S., Griffin, W.L., Sibley, S.J.Pink color in Type I diamonds: is deformation twinning the cause?American Mineralogist, Vol. 100, pp. 1518-1527.Australia, South America, VenezuelaDeposit - Argyle, Santa Elena
DS1511-1843
2015
Huang, J-H., Huang, F., Evans, L., Glasauer, S.Vanadium: global (bio)geochemistry.Chemical Geology, Vol. 417, pp. 68-89.MantleMineralogy

Abstract: Redox-sensitive transition group elements are involved in almost all fundamental geochemical processes. Of these elements, vanadium (V) contributes a particularly powerful tool to decipher the Earth's history and its link to extraterrestrial bodies. A comprehensive view of V includes the formation and interaction between the Earth's interior layers, the evolution of the Earth's surface to a habitable zone, biogeochemical cycling, and anthropogenic impacts on the environment. Tracing the geochemical behavior of V through the Earth's compartments reveals critical connections between almost all disciplines of Earth sciences. Vanadium has a history of application as a redox tracer to address the early accretion history of the Earth, to identify connections between the mantle and crust by subduction and melting, and to interpret past surface environments. The geochemical cycling of V from the deep Earth to the surface occurs through magmatism, weathering and digenesis, reflecting variations of fO2 and V species in different Earth compartments. Minerals form a link between deep Earth reservoirs of vanadium and surface environments, and the study of V in minerals has increased the understanding of V cycling. Finally, the exploitation of V has been increasing since the Industrial Revolution, and significant amounts of V have been released as a consequence into natural systems. Environmental concerns are promoting new areas of research to focus on V cycling between water, air, soil and sediment compartments. An increased understanding of V in all compartments, and knowledge of the processes that connect the compartments, is vital to tracing the fate of this intriguing element in natural systems.
DS1502-0063
2014
Huang, J-X., Li, P., Griffin, W.L., Xia, Q-K, Greau, Y., Pearson, N.J., O'Reilly, S.Y.Water contents of Roberts Victor xenolithic eclogites: primary and metasomatic controls.Contributions to Mineralogy and Petrology, Vol. 168, pp. 1092-1105.Africa, South AfricaDeposit - Roberts Victor
DS1502-0064
2015
Huang, L., Du, Y., Chen, G.GeoSegmenter: a statistically learned Chinese word segmenter for the geoscience domain.Computers & Geosciences, Vol. 76, pp. 11-17.TechnologyNot specific to diamonds
DS1506-0274
2015
Hudgins, T.R., Mukasa, S.B., Simon, A.C., Moore, G., Barifaijo, E.Melt inclusion evidence for CO2 rich melts beneath the western branch of the East African Rift: implications for long term storage of volatiles in the deep lithospheric mantle.Contributions to Mineralogy and Petrology, Vol. 169, 5p.Africa, East AfricaBasanites, Foidites
DM1506-0783
2015
Huffington PostOntario's only diamond mine and royalties paid in the province. VictorHuffington Post, May 14, 3p.Canada, OntarioNews item - De Beers
DS1505-0251
2015
Hwang, S-L., Shen, P., Chu, H-T., Yui, T-F., Lizuka, Y.Origin of rutile needles in star garnet and implications for interpreation of inclusion textures in ultrahigh pressure metamorphic rocks.Journal of Metamorphic Geology, Vol. Pp. 249-272.TechnologyUHP
DS1508-0360
2015
Hystad, G., Downs, R.T., Hazen, R.M.Mineral species frequency distribution conforms to a large number of rare events model: prediction of Earth's missing minerals.Mathematical Geosciences, Vol. 47, no. 6, pp. 647-661.TechnologyNot specific to diamonds but interesting reading!
DS1507-0316
2015
Ickert, R.B., Stachel, T., Stern, R.A., Harris, J.W.Extreme 18O-enrichment in majorite constrains a crustal origin of transition zone diamonds.Geochemical Perspectives Letters, 1, pp. 65-74.Africa, South AfricaDeposit - Jagersfontein
DS1505-0252
2015
ICMMEngaging with society - ICMM releases annual review 2014.ICMM, March, 14p. PdfGlobalCSR
DS1509-0400
2015
ICMMThe role of mining in Ghana's future.ICMM, July 72p.Africa, GhanaLegal
DS1512-1928
2015
ICMMGood practice guide to indigenous peoples and mining.ICMM , pdf. 138p.GlobalCSR
DS1503-0150
2015
ICMM, Raw Materials Group, Oxford Policy ManagementThe role of mining in national economies. 2nd editionICMM, Oct. 56p.GlobalEconomics
DM1503-0784
2015
Idex MagazineSo near yet so far … introduction to Zimbabwe diamond supplier.Idex Magazine, Feb. pp. 36-38.Africa, ZimbabweNews item - history
DM1503-0785
2015
Idex MagazineZimbabwe diamond industry.Idex Magazine, Feb. pp. 38-45.Africa, ZimbabweNews item - diamond industry
DM1503-0786
2015
Idex MagazineDiamond - sector objectives.Idex Magazine, Feb. pp. 46-51.Africa, ZimbabweNews item - legal
DM1503-0787
2015
Idex MagazineIs the Marange party over?Idex Magazine, Feb. pp. 52-61.Africa, ZimbabweNews item - Marange
DM1503-0788
2015
Idex MagazineA century of Zimbabwe diamond exploration.Idex Magazine, Feb. pp. 62-68.Africa, ZimbabweNews item - history
DM1504-0789
2015
Idex MagazineThe millennial generation.. Changing the way we buy. Idex Magazine, March, pp. 36-64.GlobalNews item - retail
DM1505-0790
2015
Idex MagazineFrom clicks to bricks - Blue Nile.Idex Magazine, Apr. pp. 38-45.GlobalNews item - Blue Nile
DM1505-0791
2015
Idex MagazineGet moving to mobile.Idex Magazine, Apr. pp. 46-55.GlobalNews item - online for consumers
DM1505-0792
2015
Idex MagazineFrom on-line to in-store: could click and collect be the next big thing?Idex Magazine, Apr. pp. 56-62.GlobalNews item - online for consumers
DM1507-0793
2015
Idex Magazine2014: the year of confidence lost.Idex Magazine, June pp. 38-43.GlobalNews item - markets
DM1507-0794
2015
Idex MagazineThe 2014 diamond pipeline.Idex Magazine, June pp. 44-66.GlobalNews item - pipeline
DM1509-0795
2015
Idex MagazineA splintering of the pipeline.. Publicity surrounding the Diamond Producers Association.Idex Magazine, Aug. pp. 36-45.GlobalNews item - pipeline
DM1509-0796
2015
Idex MagazineDanger of product substitution…Idex Magazine, Aug. pp. 46-53.TechnologyNews item - Lab grown
DM1509-0797
2015
Idex MagazineLab-grown diamonds increase bargaining power.Idex Magazine, Aug. pp. 54-66.TechnologyNews item - synthetics
DS1501-0015
2014
Idex MagazineReview of the year.Idex Magazine, No. 296, December pp. 36-66.GlobalIndustry - problems and highs and lows
DS1501-0016
2014
Idex MagazineIdex & AdAmiA .. Launch of diamond investment product.Idex Magazine, No. 296, December p. 21. ( 1p)GlobalAdAmia
DS1506-0275
2015
Idex MagazineThe missing gap, a bridge from gemology to reality.Idex Magazine, No. 301, pp. 118-119.TechnologyGemology
DS1512-1929
2015
Idex Magazine2015 Indian diamond industry Local pressures and global challenges.Idex Magazine, No. 307, pp. 34-36.IndiaEconomics
DS1512-1930
2015
Idex MagazineReturn to generalized system of preferences. IndiaIdex Magazine, No. 307, pp. 37-43.IndiaEconomics
DS1512-1931
2015
Idex MagazineRough price stability will return prosperity to the Indian diamond industry.Idex Magazine, No. 307, pp. 44-46.IndiaEconomics
DM1501-0798
2014
Idex MemoDull name, important task: generic marketing critical to industry's future.Idexonline.com, Dec. 4, 1p.GlobalNews item - markets
DM1501-0799
2014
Idex MemoGIA battling crimes: suspends duplicate report service to prevent fraud.Idexonline.com, Dec. 11, 2p.GlobalNews item - GIA
DM1501-0800
2014
Idex MemoLong path to recovery shows few signs of ending for Japan. Idexonline.com, Dec. 19, 2p.JapanNews item - economics
DM1502-0801
2014
Idex MemoYear end reflections: the 95 year struggle to secure rough for beneficiation.Idexonline.com, Dec. 25, 2p.Global, IndiaNews item - rough demand
DM1502-0802
2015
Idex MemoNew Year, old challenges. Idexonline.com, Jan. 1, 2p.GlobalNews item - demand
DM1502-0803
2015
Idex MemoTrue Luxe ways. Study on luxury brands and their best customers.Idexonline.com, Jan. 8, 1p.GlobalNews item - markets
DM1502-0804
2015
Idex MemoModern family…. Tiffany's ad campaign.Idexonline.com, Jan. 15, 2p.GlobalNews item - Tiffany
DM1502-0805
2015
Idex MemoA way with words… engagement marketingIdexonline.com, Jan. 22, 1p.TechnologyNews item - markets
DM1503-0806
2015
Idex MemoEconomics 101: a course on added value.Idexonline.com, Jan. 29, 2p.TechnologyNews item - economics
DM1503-0807
2015
Idex MemoSynthetic diamond producer creates trade representative body prohibits the use of the 'S'-word.Idexonline.com, Feb. 12, 8p.TechnologyNews item - synthetics
DM1503-0808
2015
Idex MemoToo much of a good thing? Re-used engagement rings.Idexonline.com, Feb. 19, 1p.GlobalNews items - engagements
DM1504-0809
2015
Idex MemoUndisclosed lab-grown diamonds strike again. SuratIdex Online, Feb. 26, 1p.IndiaNews item - synthetics
DM1504-0810
2015
Idex MemoIs it just history repeating itself? ( promotion)Idex Online, Mar. 12, 1p.GlobalNews item - promoters
DM1505-0811
2015
Idex MemoJust a little disruption… discusses DDI's approach and work to date.Idex Online, Apr. 2, 1p.GlobalNews item - DDI
DM1505-0812
2015
Idex MemoIf you have to pinpoint three factors from the diamond business affecting the retail world of fine jewelery, what would you pick?Idex Online, Apr. 9, 1p.GlobalNews item - jewellery
DM1505-0813
2015
Idex MemoGoing up or down: where are diamond prices really headed?Idexonline.com, Apr. 16, 1p.GlobalNews item - prices
DM1505-0843
2015
Idex MemoRocking the boat… Marques de Morais overview.Idex Online, Mar. 26, 1p.Africa, AngolaNews item - legal
DM1506-0814
2015
Idex MemoTaxing the Antwerp diamond industry into prosperity.IdexOnline, Apr. 23. 3p.Europe, BelgiumNews item - legal