Resource World Magazine

The Gaucho Kué exploration camp in the Lac de Gras region of the Northwest Territories, a joint venture between Mountain Province and De Beers Canada. Photo courtesy Mountain Province Diamonds Inc. NWT DIAMOND DEVELOPMENTS Diamond exploration around the Northwest Territories' Lac de Gras diamond fields shows exceptional potential to extend mine production for many years. by Edward Schiller PhD Diamonds were first discovered in Canada's Northwest Territories in September 1991. The 9th of September to be exact as I had the fortunate task of drilling the discovery hole for Diamet Minerals Ltd. at Point Lake that led to discovery of the Ekati diamond mine with partner BHP Minerals. Ekati, about 300 km northeast of Yellowknife, the capital of NWT, opened in 1998 within the now famous diamond fields of Lac de Gras. The Point Lake kimberlite (the host rock of diamonds) did not become a mine; however, it led to the discovery of several producing kimberlites on the property. In 2003, the nearby Diavik diamond mine commenced production; operated by Rio Tinto PLC [RIO-NYSE, ASX] and Aber Resources Ltd. In 2010 and 2013, both mines, respectively, were acquired in part by Dominion Diamond Corp. [DDC-TSX], formerly known as Harry Winston Diamond Corp. and before that Aber Resources. This was followed by the NWT's third producing mine at Snap Lake, discovered in 1996 by Winspear Resources Ltd. and acquired by De Beers Canada in 2000. Snap Lake, located 220 km northeast of Yellowknife, came into production in 2008 as an underground mine with proven and probable resources of 22,800,000 tonnes containing 33,288,000 carats at a grade of 1.46 carats per tonne. The Lac de Gras diamond discoveries prompted one the world's biggest staking rushes and resulted in Canada becoming a major diamond producer. 44 www.resourceworld.com RW December 2013.indd 44 In the adjoining Territory of Nunavut, Tahera Diamond Corp. operated the Jericho diamond mine from 2006 to 2008 and produced 780,000 carats of diamonds. An attempt to reopen the mine by Shear Diamonds Ltd. in 2010 failed and operations were suspended indefinitely. Diamond exploration has continued in the NWT and the next producing mine in the making will be at Gaucho Kué where Mountain Province Diamonds Inc. [MPV-TSX; MDM-NYSE MKT], 49%, and operator De Beers Canada, 51%, have received approval to proceed with the development of the project. Full production at Gaucho Kué is expected to commence by the second quarter of 2015. The project, deemed to be the world's largest and richest new diamond mine, has probable reservets of 49 million carats based on a grade of 1.57 carats per tonne, yielding 4.5 million carats per year over an 11-year period from open pits. The project comprises four kimberlite pipes of which the following three have established probable reserves. The fourth pipe, Telsa, is not included because it is small (0.4 hectares) but in the future it could be exploitable with more drilling. The approved mine plan for Gaucho Kué only considers open pittable reserves to a depth of approximately 300 metres. The resource potential available to underground mining, when developed, will extend the life of mine considerably. Pipe Category tonnes (millions) carats (millions) grade (cpt) 5034 probable 13.2 23 1.77 Hearne probable 5.4 11.5 2.10 Tuzo probable 12.6 14.2 1.13 Summary probable 31.3 49.0 .57 DECEMBER/JANUARY 2014 12/11/2013 6:12 PM

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