Drills connect the deposits at Bornite

Trilogy Metals Inc. Dec. 13 said results from the final five holes drilled this year at Bornite continue to show the potential to expand the high-grade underground resource at this world-class copper-cobalt project in the Ambler Mining District of Northwest Alaska, including toward the open-pit deposit to the south.

"The latest drilling results confirm the extent and continuity of the copper and cobalt mineralized system at the Bornite Project, and continue to demonstrate that the system is open," said Trilogy Metals President and CEO Rick Van Nieuwenhuyse.

According to a 2016 calculation, the open-pit deposit at Bornite contains 40.5 million metric tons of indicated resource averaging 1.02 percent (913 million pounds) copper; and 141.9 million metric tons of inferred resources averaging 1.74 percent (5.45 million lb) copper.

The deposit also hosts 182.4 million metric tons of inferred resource averaging 0.019 percent (77 million lb) cobalt, according to a resource calculated for the battery metal earlier this year.

The underground portion hosts 57.8 million metric tons of inferred resource averaging 2.89 percent (3.68 billion lb) copper and 0.025 percent (32 million lb) cobalt.

Much of this year's drilling focused on expanding the high-grade underground resource to the north.

In this latest batch of results, hole RC18-0254 cut seven mineralized intercepts from 455 to 767.3 meters in the northern underground resource area: 123.9 meters averaging 1.07 percent copper and 0.02 percent cobalt; 10 meters averaging 0.81 percent copper and 0.04 percent cobalt; 13.5 meters averaging 0.78 percent copper and 0.01 percent cobalt; 46 meters averaging 0.98 percent copper and 0.01 percent cobalt; eight meters averaging 0.91 percent copper and 0.01 percent cobalt; and 29 meters averaging 1.68 percent copper and 0.04 percent cobalt.

Hole 254 was drilled about 150 meters south of RC13-0224, a 2013 hole that cut 236 meters averaging 1.9 percent copper, including 6.6 meters of 7.7 percent copper.

"The results from drill hole RC18-0254 show additional thick zones of continuous copper-cobalt mineralization which is what was seen in RC13-0224," said Van Nieuwenhuyse.

Another three holes of the 2018 program – RC18-0252, RC18-0255 and RC18-0256 – targeted an area of sparse drilling between the Bornite open-pit and underground resources.

RC18-0255, the northern most of these holes intersected four mineralized intervals between 256.9 and 255.6 meters: one meter averaging 11.47 percent copper and 0.02 percent cobalt; 5.4 meters averaging 0.88 percent copper and 0.02 percent cobalt; 14.3 meters averaging 0.97 percent copper and 0.01 percent cobalt; and 3.1 meters averaging 1.96 percent copper and 0.02 percent cobalt.

RC18-0252, drilled about 200 meters south of hole 255, cut five mineralized intervals between 178.3 and 210.2 meters: 2.9 meters averaging 1.95 percent copper and 0.03 percent cobalt; 3.6 meters averaging 2.63 percent copper and 0.02 percent cobalt; 12.5 meters averaging 1.49 percent copper and 0.03 percent cobalt; 1.9 meters averaging 1.12 percent copper and 0.02 percent cobalt; and 7.5 meters averaging 2.25 percent copper and 0.02 percent cobalt.

RC18-0256, drilled about 150 meters southwest of hole 252, cut three mineralized intervals between 165.7 and 271.2 meters: 12.9 meters averaging 0.94 percent copper and 0.02 percent cobalt; 6.6 meters averaging 1.36 percent copper and 0.02 percent cobalt; and 15 meters averaging 2.54 percent copper and 0.02 percent cobalt.

"These three drill holes extend the mineralized envelope towards the surface - potentially expanding the open-pit resource," said Van Nieuwenhuyse.

RC18-0251, drilled at the margins of the Bornite deposit about 300 meters southeast of hole 252 cut three mineralized intervals between 539.1 and 677.3 meters of: 13.6 meters averaging 0.72 percent copper and 0.01 percent cobalt; 1.7 meters averaging 1.01 percent copper; and 1.3 meters averaging 0.98 percent copper and 0.04 percent cobalt.

"The results from RC18-0251 extend the South Reef Zone up-dip to the south – albeit at lower grades but the mineralized system remains open up-dip towards the surface," the Trilogy Metals CEO added.

Trilogy said holes 251, 252, 255 and 256 that the deeper underground resource is open up-dip and joins the shallower open-pit deposit at Bornite.

This year's 10,123-meter drill program at Bornite was funded by South32 Ltd., which has an option to acquire a 50 percent interest in the Upper Kobuk Mineral Projects for US$150 million.

To keep this option in good standing, the Australian miner has agreed to invest US$30 million at Upper Kobuk Mineral Projects over a three-year span that began in 2017

So far, South32 has invested US$20.8 million on exploration at Bornite, including an 8,347-meter expansion drill program at Bornite, leaving US$9.2 million for 2019.

–SHANE LASLEY