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 announcements called 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 SDLRC Blog is a guest commentary by an industry expert about articles, themes and trends in recent issues of the SDLRC.
Comments by Brooke Clements
Brooke Clements received a B.Sc in Geology from Indiana University and an M.Sc in Economic Geology from the University of Arizona. From 1982 to 1997, he was an Exploration Geologist and Regional Manager for Exmin Corporation where he conducted diamond exploration programs throughout the United States. From 1998 to 2007 he was Vice President, Exploration for Ashton Mining of Canada Inc. Under his leadership, the Ashton-SOQUEM exploration team discovered the Renard diamond district in Quebec where Stornoway Diamonds opened the Renard Diamond Mine in 2016. From 2007 to 2015 he was President of Peregrine Diamonds Ltd. where he led the team that discovered the Chidliak diamond district on Baffin Island in the Canadian Arctic. Currently, Brooke is President of JBC Ventures Ltd., a consulting company specializing in mineral exploration and community and government relations. He is also President and CEO of Craton Minerals Ltd., a private diamond exploration company focused on discovering North America's next new diamond district.
Brooke Clements has volunteered to highlight the scientific articles that caught his attention in the monthly reference compilations. The opinions expressed are solely his and he can be reached at .
This paper is a good reference for those with interest in diamond exploration in the 13 Gondwanaland Archean cratons (Africa, Australia, Greenland, India and Antarctica). Exploration in Antarctica will make the arctic look like child's play. There are good summaries with references of the crustal structure and properties of the cratons. The authors suggest that the Moho depth within cratons is less uniform than previously thought (28-52 km) and early and middle Archean undeformed crust is characterized by a shallow Moho depth (28--38 km), while late Archean or deformed crust may be as thick as 52 km.
Green natural diamonds are extremely rare and very little information on them is available. On November 28, 2017 Peregrine Diamonds created a buzz with the reporting of a green diamond in a mini-bulk sample from their Chidliak property. This paper, which is a free download, tells you everything you want to know (and more) about rare green diamonds. The GIA has information for 50,000 diamonds with a green hue, including 9,000 pure green diamonds in their database. The green color is caused by simple structural defects caused by radiation exposure or more complex defects resulting from nitrogen, hydrogen or nickel impurities. It is very hard to tell a natural green diamond from a treated diamond because the defects causing the color are the same in nature and the laboratory. Green diamonds are the largest category of colored diamonds that are classified as having "undetermined" color origin by gemological labs.
This paper is a free download and a very good read for someone wanting summary information on parts of Russia and Finland comprising the northern east European platform. After analyzing available geophysical data and the physical and chemical traits of 1513 indicator minerals recovered from over 6,000 stream sediment samples, the authors conclude that the northern East European platform is a good target for more diamond exploration. Included is a link to the indicator mineral data (without locations).
This paper was presented at the kimberlite conference in Botswana and it created quite a buzz when it was postulated that the age of the diamonds at the Victor Mine are 720 million years. The diamonds are mostly lherzolitic and thought to be from a 10 km thick layer at about 180 km depth. A paper by Aulbach et al. tabulated in last month's Sheahan review is related.