North of 60 Mining News - The mining newspaper for Alaska and Canada's North

Trilogy Metals Inc. April 25 reported that the Arctic deposit at its Upper Kobuk Mineral Projects in Northwest Alaska now contains 2.4 billion pounds of copper and 3.4 billion lb of zinc in the indicated resource category, a roughly 40 percent increase for both metals.

At a 0.5 percent copper-equivalent cut-off grade, the Arctic deposit is estimated to contain in-pit 36 million metric tons of in-pit indicated resources averaging 3.07 percent (2.4 billion lb) copper, 4.23 percent (3.4 billion lb) zinc, 0.73 percent (581 million lb) lead, 0.63 grams per metric ton (728,000 oz) gold and 47.6 g/t (55 million oz) silver.

"The resource is not sensitive to cut-off grade or metal prices at the ranges investigated, since a 300 percent increase in cut-off grade results in less than a 1 percent decrease in contained metal at higher average grades. That is a robust deposit," said Trilogy Metals President and CEO Rick Van Nieuwenhuyse.

Additionally, this volcanogenic massive sulfide deposit hosts 3.5 million metric tons of inferred resources averaging 1.71 percent (131 million lb) copper, 2.72 percent (210 million lb) zinc, 0.6 percent (47 million lb) lead, 0.36 g/t (29,000 oz) gold and 28.7 g/t (3 million oz) silver.

Trilogy Metals has budgeted US$7.2 million for a 2017 work program that will focus on finalizing a prefeasibility study on developing an open-pit mine at Arctic.

Additionally, South32 Ltd. is investing roughly US$10 million on exploration of Bornite, a high-grade copper deposit about 16 miles south of Arctic.

South32 has the option to earn up to a 50 percent stake in the Upper Kobuk Mineral Projects by investing up to US$150 million in this expansive Northwest Alaska project over the next three years.

-SHANE LASLEY