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 is President and CEO of Craton Minerals Ltd., a Vancouver-based private diamond exploration company focused on discovering North America's next diamond district. He is also President of JBC Ventures Ltd., a consulting company specializing in mineral exploration and community and government relations. 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. Before that, Brooke was Vice President, Exploration for Ashton Mining of Canada Inc. Under his leadership, Ashton and their partner SOQUEM discovered the Renard diamond district in Quebec where the Renard Diamond Mine commenced production in 2016. From 1982 to 1997, Brooke was an Exploration Geologist and Regional Manager for Exmin Corporation where he conducted diamond exploration programs throughout the United States. He holds a BSc in Geology from Indiana University and an MSc in Economic Geology from the University of Arizona.
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 .
The paper has a good discussion on the Reasonable Prospects for Eventual Economic Extraction (RPEEE) requirement for disclosure of a resource based on South African (SAMREC) requirements. Dr. Lock stated the following regarding diamond valuations: "The use or misuse of old diamond valuation reports is perhaps the single most problematic aspect of bad practice. Unlike other commodities where the price is date-specific, diamond value is deposit-specific as well as date-specific. Indeed, any diamond valuation is also subject to the effect of bottom cut-off screen size." SAMREC requires that valuation reports used in resource statements be less than six months old. Case studies from five projects are presented: Brauna, Brazil, Messina/Star, South Africa, Letsang, Lesotho, Koidu, Sierra Leone and Lace, South Africa.
A good summary of the interpretation of ground magnetic and gravity data over two relatively small kimberlites within the Orapa field in Botswana that are buried under a layer of basalt measuring over 75 metres thick.
This is a fulsome discussion of evaluating and defining a resource for an alluvial diamond project. Over the last decade, a number of alluvial diamond projects (fluvial and marine) in Africa have been developed by public companies so there is a need to document the projects in a code-compliant manner. Most alluvial deposits have been worked by artisanal operators and there has been a belief that accurate resource estimates are impossible. One difficulty encountered when evaluating an alluvial deposit is a lack of accurate historical sampling data. The South African Code for the Reporting of Exploration Results, Mineral Resources and Mineral Reserves (SAMREC) has several sections to assist with code-compliant resource estimation.
Very good summary of plant issues etc. Colorado-based Howard Coopersmith is a well-known consultant with expertise in diamond plant optimization and quality control.He provided me the following comments on this paper: "This paper discusses the important factors in diamond ore processing and recovery, and some attempts at their quantification. Such data, analysis and knowledge is critical in applying aspects of Diamond Value Management at a diamond operation. Such data and knowledge is rarely discussed in the literature. At some operations, due to budgetary and personnel limitations, and perhaps the desire to not know what we don't know these considerations are unfortunately not part of the daily conversation. Dellas is to be commended for bringing this discussion to the table."