Tap wide zone of strong mineralization NE of planned open pit North of 60 Mining News – November 24, 2021
Trilogy Metals Inc. Nov. 22 reported that assay results from two holes drilled this year at the Upper Kobuk Mineral Projects in Northwest Alaska tapped high-grade mineralization beyond the current pit at the Arctic Mine project.
A 2020 feasibility study for developing a mine at Arctic details a financially robust operation that would produce 1.9 billion pounds of copper, 2.3 billion lb of zinc, 388 million lb of lead, 386,000 ounces of gold, and 40.6 million oz of silver over an initial 12-year mine life.
This operation is based on 43 million metric tons of reserves averaging 2.32% copper, 3.24% zinc, 0.57% lead, 0.49 grams per metric ton gold, and 36 g/t silver.
While high-grade volcanogenic massive sulfide deposits such as Arctic are typically mined from underground, the Arctic feasibility study details plans for a lower cost open-pit mine feeding a 10,000-metric-ton-per day mill.
Ambler Metals LLC, a joint venture operating company equally owned by Trilogy and South32 Ltd., completed an 18-hole (4,131 meters) diamond drill program this year designed to upgrade a portion of the indicated resources at Arctic to the higher confidence measured category, as well as provide material for metallurgical testing and geotechnical information.
“The latest drilling program at Arctic will assist Ambler Metals in the continued de-risking of the project and in the detailed engineering of the asset,” said Trilogy Metals President and CEO Tony Giardini.
The first assay results are from two geotechnical holes, AR21-0173 and AR21-0175, drilled to test the stability of the pit wall on the northeast side of the proposed Arctic Mine. Both encountered high-grade mineralization beyond the currently defined pit at Arctic.
Hole AR21-0173 cut 3.77 meters averaging 2.15% copper, 0.87% zinc, 0.34% lead, 0.83 g/t gold, and 82.89 g/t silver from a depth of 110.5 meters at the north edge of the deposit. This hole shows that one of the high-grade zones in the mine plan extends north just below the proposed open pit.
Hole AR21-0175 cut three of the high-grade zones on the northeast edge of the proposed open pit. From a depth of 71.9 meters, this hole cut 24.94 meters averaging 1.85% copper, 2.96% zinc, 0.57% lead, 0.28 g/t gold, and 27.09 g/t silver from a depth of 71.9 meters.
This includes 5.62-meter higher-grade subinterval averaging 4.94% copper, 10.57% zinc, 1.71% lead, 0.4 g/t gold, and 58.9 g/t silver.
“The initial drilling results from Arctic continue to confirm our belief that the Arctic deposit is one of the highest grade polymetallic mineral projects in the world,” said Giardini. “Not only is Arctic high-grade, but it also has wide zones of mineralization that are relatively close to surface.”
With the slow turnaround time at assay labs, these are the first results from the 2021 drill program at UKMP.
“It is good to see the results of our 2021 drill program are beginning to come in from ALS Laboratories. Also, good to see these high-grade extensions, just outside the proposed pit and relatively close to surface, in holes that were primarily designed to collect geotechnical information,” said Trilogy Metals Vice President of Exploration Richard Gosse. “We are looking forward to seeing the results of the remaining 16 drill holes at Arctic as well as from the regional drill program.”