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 .
This is a pre-print of an interesting, very detailed study of alluvial diamonds recovered from a number of places in the rainforest of Guyana on the Guiana Shield. The stones in the study were .3-2.7 mm in size and are thought to have been eroded from Paleoproterozoic metamorphosed conglomerates. Based on inclusion studies both eclogitic and peridotite diamonds are present. Associated minerals in the alluvial deposits are non-kimberlitic including zircons which were dated and interpreted to be from Paleoproterozoic rocks that are about 2.0 billion years old. There is a good summary of diamond deposits in Guyana and the associated geology and some speculation on potential sources.
Thirteen diamonds recovered from a creek in northeastern Suriname on the Guiana Shield were studied. Mineral inclusion assemblages suggest a peridotitic paragenesis. The source of the diamonds is unknown and there are two possibilities, conglomerates in the area or a primary ultramafic source. The authors suggest the diamonds experienced extended sedimentary transport from a distal primary source.
Experiments to assess the mechanical stability of olivine, garnet, orthopyroxene, clinopyroxene and diamond during kimberlite magma ascent were conducted. The model derived from the experiments was applied to natural garnet and olivine xenocrysts and a velocity of four meters per second was determined for ascending kimberlite magma.