De Beers Identifies New Kimberlite Indicator

RAPAPORT... The discovery of a new source-rock indicator for diamondformation has the potential to help geologists locate and identify valuablediamond deposits around the world, a study by the University of Alberta and DeBeers shows. "The outcome of the project fundamentally changes ourunderstanding of where diamonds come from," Thomas Stachel, a University ofAlberta geologist and the Canadian research chair for diamonds, was quoted as saying in an online article published by Phys.org. "[It] has the potential to cause diamondcompanies to retool their approach to exploration." Geologists at Canada's University of Alberta studieda sample of 116 diamonds from De Beers' Victor mine in Ontario. The goal was tocharacterize the sample's mineral inclusions and identify any that could beage-dated using their isotopic compositions, which could serve as indicatormaterials for kimberlite. Of the stones tested, 99 showed garnet inclusions, a typicalindicator for diamonds. However, 85% of those garnet samples were found to be lherzolite,a peridotitic rock that had previously been discovered around diamond areas,but had been considered unimportant. "This makes Victor the first significant diamond mine in theworld that extracts a predominantly lherzolite-derived diamond production," thestudy notes. Lherzolite rock has been identified in other areas ofCanada, including Buffalo Head Hills in Alberta and the Saskatchewan region,Tom Ormsby, head of external and corporate affairs for De Beers Canada, told RapaportNews Tuesday. It is also found at mining sites such as Ellendale in WesternAustralia and De Beers' Venetia in South Africa, according to the study. "In the long run, this could make a big difference indiamond exploration," Stachel explains. The University of Alberta is also studying inclusions from DeBeers' Snap Lake and Gahcho Ku?(C) mines in Canada that will enable them toidentify and separate "barren" lherzolite from the diamondiferous kind usingmachine learning, Ormsby added. Image: De Beers' Victor mine. (De Beers)