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

Fireweed Zinc Ltd. June 20 announced that crews have been mobilized for the company's largest drill program so far at the Macmillan Pass property in Yukon, Canada.

"We are very excited to start our 2022 season," said Fireweed Zinc Vice President of Exploration Gilles Dessureau. "It will be the largest and most ambitious program ever carried out by Fireweed at the Macmillan Pass project."

The 544-square-kilometer (210 square miles) Macmillan Pass property blankets a roughly 55-kilometer (34 miles) trend of zinc, lead, and silver mineralization just west of the Northwest Territories border.

Two of its more advanced deposits – Tom and Jason – host 11.2 million metric tons of indicated resource averaging 6.59% (1.63 billion pounds) zinc, 2.48% (620 million lb) lead, and 21.33 grams per metric ton (7.7 million ounces) silver; plus 39.5 million metric tons of inferred resource averaging 5.84% (5.08 billion lb) zinc, 3.14% (2.73 billion lb) lead, and 38.15 g/t (48.4 million oz) silver.

"The main objectives of the 2022 field program will be to define and expand the known mineralized zones toward an updated mineral resource study this winter followed by an updated preliminary economic study," added Dessureau. "We are also excited to use innovative new technologies, such as muon tomography and hyperspectral imaging to guide exploration."

Toward this objective, the C$10-million (US$7.7 million) 2022 drill program will include approximately 8,000 meters of drilling with four rigs testing several target areas.

The first three drills are slated to complete roughly 5,800 meters of drilling at Boundary and Boundary West, prospective zones about 15 road kilometers (nine miles) west of Jason that has shown potential for expansion of its current resource and were the primary focus of Fireweed's drilling over the previous two seasons.

Some past highlights from previous drilling at Boundary and Boundary West include:

• 230 meters averaging 4.14% zinc from surface in hole NB19-002 (Boundary).

• 213 meters averaging 3.72% zinc in hole NB20-002 (Boundary).

• 3.7 m meters averaging 4.76% zinc in the upper sequence and 225 meters averaging 2.08% zinc in lower sequence in hole NB20-009 (West Boundary).

• 33 meters averaging 9.91% zinc in hole NB21 -002.

Because Boundary is open in every direction, the 2022 program has been designed to test step-outs around the peripheries of Boundary Main and Boundary West, in addition to testing a potential connection between the two zones.

The step-outs will include testing potential down-dip continuation of the recently discovered Boundary West, and testing for additional massive sulfide mineralization near surface.

To help guide the 2022 drilling, Fireweed is employing the use of cutting-edge muon detectors to target step-outs and help define the geometry of the recently discovered zones of massive and high-grade laminated sulfide at Boundary West.

The company has enlisted the help of Ideon Technologies to define the geometry of known zinc mineralization at Boundary West, and target additional mineralization in the area. Muon tomography is a down-hole geophysical technique that uses naturally occurring cosmic-ray muons to measure density contrasts and identify subsurface anomalies such as dense bodies of zinc mineralization.

In addition to drilling the Boundary zones, a fourth rig is slated to complete approximately 2,300 meters of drilling at the Tom West, Tom North, Jason Main, and Jason South zinc-lead-silver deposits.

The drilling at Tom West will focus on infilling high-grade zones where the current mineral resource is supported by small-diameter historical diamond drilling with very poor recovery in the higher-grade portions of the holes.

Additionally, Fireweed says it sees potential to increase the zinc, lead, and silver grades in these areas by drilling large HQ diameter holes using triple-split tubes to improve recovery, as demonstrated with previous drill programs.

The drilling at Tom North will step out from the near-surface mineralization that is potentially amenable to open-pit mining, while the drilling at Jason Main and Jason South will step out from known high-grade mineralization.

By the end of the program, Fireweed will have four seasons worth of new drill data that will be used to inform a new global mineral resource, including an inaugural resource for the Boundary Main, Boundary West, End Zone, and Tom North zones, as well as an updated resource for Tom West, Tom East, Tom Southeast, Jason Main, and Jason South zones.

The company plans to use this resource as the basis for a preliminary economic assessment that provides an initial look at establishing a mine at Macmillan Pass.

In addition to the drilling, all core from the 2022 program, plus previous Fireweed and historical drilling, will be scanned using advanced hyperspectral scanning technology.

Fireweed Zinc Ltd.

Click image to see larger map.

Working with GeologicAI, the scanning will include high-resolution digital photography, lidar topography, shortwave, visible, and near-infrared hyperspectral imagery, and X-ray fluorescence (XRF) scans.

Fireweed hopes using this information to inform geometallurgical models of the deposits will assist in optimizing the upcoming PEA.

Beyond carrying out the largest drill program at Macmillian Pass, field crews will also be conducting due diligence and validation work at the recently acquired Mactung tungsten project this year in preparation for a planned mineral resource update and PEA study on this neighboring property.

You can read about Fireweed's purchase of Mactung at Fireweed Zinc cuts deal to buy Mactung in the June 10, 2022, edition of North of 60 Mining News.