Amidst a period of global uncertainty, the Northwest Territories (NWT) mining sector continued to exhibit optimism with a series of new kimberlite discoveries.
One of the indicators of notable gains in exploration activity –claims staked vs. lapsed – continued an upward trend that began in 2017. In the first three quarters of 2019, 120 claims covering 45,000 hectares were added, and there are 37 active Prospecting Permits this year. New staking included large areas in the Mackenzie Mountains, additional ground at Pine Point, re-staking of claims in the Lac de Gras region, and expansion of claims in the Yellowknife area.
New Kimberlite Discoveries
The Lac de Gras project, a joint venture between Dominion Diamonds Mines (79 per cent) and North Arrow Minerals Inc. (21 per cent), conducted a spring ground geophysics program and follow-up drilling program, which intersected a kimberlite on the first drill hole. In June 2019, the De Beers Canada (51 per cent) and Mountain Provinces Diamonds (49 per cent) Gahcho Kué Mine JV announced the discovery of the diamondiferous Wilson kimberlite pipe located roughly 200 metres east of the Tuzo kimberlite, within the current mine plan area.
Exploration work in 2018 led to a new kimberlite discovery by North Arrow Minerals Inc. on the Loki project in the Lac de Gras region. Exploration in 2019 consisted of prospecting, till sampling, and ground geophysics to confirm and prioritize targets for follow up 2020 winter exploration drilling.
Diagras property, a Margaret Lake Diamonds (60 per cent) and Arctic Star Exploration Corp. (40 per cent) joint venture at Lac de Gras completed ground gravity, magnetic and EM surveys around known kimberlites to identify new phases, as well as completely new targets for drill testing in spring 2020.
NWT Diamond Mine Production
Gahcho Kué experienced better than forecast production with over 20 million total tonnes mined and a diamond production of over 3.3 million carats (an average grade of 1.89 carats/ tonne) for the first half of 2019.
During the first half of 2019, Diavik Diamond Mines, owned by Rio Tinto (60 per cent) and Dominion Diamonds (40 per cent), processed 1,291,000 tonnes of ore and recovered 3,663,000 carats. At Diavik, carats recovered in the second quarter of 2019 were three per cent higher than the second quarter of 2018 due to higher grades and ore processing throughput.
Dominion Diamond Mines ULC (a part of the Washington Companies) continues production from the Ekati diamond mine. There is no publicly available production data at this time.
Updated Resource Estimate
Updated mineral resource details at Mountain Province Diamonds Inc.’s Kennady North project, located 10 kilometres from Gahcho Kué, bring the resource up to 5.45 million carats in 2.07 million tonnes of kimberlite, with an overall grade of 2.63 carats/tonne. This represents a 49 per cent increase in tonnage and a 74 per cent increase in total carats.
Advanced NWT gold projects benefited from high market gold prices.
Nighthawk Resource Corp. increased its 2019 drill plans from $10 million to $13 million to drill 35,000 metres at Colomac and satellite targets at Indin Lake Gold Project. All 2019 drill holes reported thus far have intersected mineralization. Initial results from Zone 1.5 showed their best intersection to date, as it intersected 56 metres of 13.49 g/t Au, including 10 metres of 53.57 g/t Au.
TerraX Minerals Inc. expanded its land holdings for its Yellowknife City Gold project to 783 square kilometres. Drilling results from Sam Otto extended gold mineralization by 600 metres of strike. These results, combined with 2018 results, show that the south zone extends for 1.2 kilometres with gold mineralization found over 2.5 kilometres along the Sam Otto structural corridor.
Sixty North Gold Mining continues to advance its MON property north of Yellowknife with trenching of several semi-massive sulphide gold-silver-lead and zinc mineralization. Evrim Resources Corp. was active on its newly discovered Astro Project along the NWT-Yukon border with geophysics and RC drilling.
High zinc demand estimates have encouraged a rejuvenation of Pine Point lead-zinc project by Osisko Metals Inc. and Norzinc Ltd.’s efforts to bring Prairie Creek into production.
Osisko Metals had a substantive exploration and drilling program at the Pine Point Project centred on airborne gravity gradiometry and a compilation of historical drill-hole data. This effort identified more than 100 drill holes with significant mineralization, indicative of near-surface mineralizing systems not previously pursued. This year, a total of 84 claims were staked which increased the project’s total surface area to 46,533 hectares, or 465 square-kilometres.
NorZinc Ltd., formerly Canadian Zinc, continued the Prairie Creek Mine Site all-season road permitting process. The deposit has a proven and probable reserve of 8.1 million tonnes of 8.6 per cent zinc, 8.1 per cent lead, and 3.6 oz./tonne silver. Resource Capital Fund has agreed to purchase a one per cent royalty on Prairie Creek Mine for C$8 million to provide funding through the completion of permitting of the project.
Rare Earth Elements
Market price improvements prompted Avalon Advanced Materials to reactivate the Nechalacho Rare Earth Elements Property at Thor Lake. Fieldwork began in July, supported by a collaborative development agreement with Australia’s Cheetah Resources Pty. Ltd. and Vital Metals Ltd. Re-logging and sampling of historic drill core was accompanied by a shipment of a stockpiled T-Zone bulk sample for metallurgical process testing.
Fortune Minerals continued to refine economic parameters on its NICO cobalt-gold-bismuth–bismuth deposit, and has concluded that a 4,650 tonne/day milling rate optimally balances economies of scale and capital costs while focusing on a smaller open pit with higher cobalt and gold grades.