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

Fireweed Zinc Ltd. Nov. 5 reported that drills cut 230 meters averaging 4.14 percent zinc from a depth of eight meters at Boundary, a zone currently not included in the resource for the company's Macmillan Pass project in eastern Yukon.

Two deposits at Macmillan Pass – Tom and Jason – host 11.21 million metric tons of indicated resource averaging 6.59 percent (1.63 billion pounds) zinc, 2.48 percent (610 million lb) lead and 21.33 grams per metric ton (7.7 million ounces) silver; plus 39.47 million metric tons of inferred resource averaging 5.84 percent (5.08 billion lb) zinc, 3.14 percent (2.73 billion lb) lead and 38.15 g/t (48.4 million oz) silver.

Situated about 15 road-kilometers (nine miles) west of the Jason deposit, Boundary has the potential to expand these resources and improve the economics of establishing a mine at this already large zinc project.

The 230-meter-long intercept in NB19-002, the second hole drilled this year at Boundary, included a 100-meter section averaging 7.94 percent zinc and 11.1 g/t silver from a depth of eight meters; and 6.4 meters of 42.49 percent zinc and 42.1 g/t silver from 139.4 meters.

NB19-001, reported by Fireweed in October, cut 250 meters of 3.44 percent zinc from the surface at Boundary, including 23.31 meters averaging 16.35 percent zinc and 27.9 g/t silver from a depth of 93.69 meters; and 11.85 meters of 9.18 percent zinc and 71.6 g/t silver from 226.2 meters.

"These results are a great way to finish the 2019 drilling at Macmillan Pass," said Fireweed Zinc CEO Brandon MacDonald. "I had previously stated that our first hole NB19-001 was the best ever drilled at Boundary and now we have eclipsed that with NB19-002. This hole is even better and clearly demonstrates zones of very high grade within a very broad interval which points to the large size and grade potential of Boundary zone."

This near surface deposit has potential to expand current mineral resources and improve the mine plan outlined in a 2018 preliminary economic assessment for MacMillan Pass.

Fireweed is currently testing the potential of using sorting technology to increase the grade of ore from Boundary fed into a future mill.

Initial test results indicate that Boundary mineralization is potentially amenable to low-cost X-Ray Fluorescence (XRF) ore sorting technology. During these tests, 50 to 70 percent of the waste material was rejected while 80 to 85 percent of the zinc was recovered. This means that the mined material averaging 2.5 percent zinc would be upgraded to 5 percent before being fed to the mill, while retaining the majority of the contained zinc.

Core collected from the two 2019 holes, assays are pending from the second hole, will be used to carry out commercial-scale ore sorting and metallurgical tests.

In addition to the two holes drilled at Boundary, the 2,357 meters of core drilling completed Tom West, which hosts the bulk of the resource in the Tom deposit, and Tom North, an expansion area not included in the resource estimate.

Drilling in both zones returned encouraging results.

"With all the data in from the summer program, we will now fully evaluate the results and consider the best path forward to advance the project," said MacDonald. "Clearly we have some potential levers to improve economics after our excellent results from the 2018 and 2019 campaigns."

–SHANE LASLEY