Fireweed’s $44M raise for Macpass and Mactung: project and infrastructure lens for engineers
Reviewed by Joe Ashwell

First reported on MINING.com
30 Second Briefing
Fireweed Metals has secured a C$61.5 million non-brokered placement from JX Advanced Metals and the Lundin Family Trusts to advance its Macpass zinc-lead-silver and Mactung tungsten projects in Yukon, plus the early-stage Gayna zinc-germanium-gallium project in the Northwest Territories. Macpass currently hosts 56 million indicated tonnes at 5.49% zinc, 1.58% lead and 24.2 g/t silver, while nearby Mactung holds 41.5 million indicated tonnes at 0.73% WO₃, with feasibility work targeting completion in early 2027. Recent backing also includes $15.8 million from the US Department of Defense and up to C$12.9 million from Canada’s Critical Minerals Infrastructure Fund to connect Macpass to the road network.
Technical Brief
- Mactung lies 13 km north of Macpass, enabling potential shared camp, access and services infrastructure.
- Macpass is ~300 km northeast of Whitehorse, so road-connection funding is critical for haulage and logistics.
- Macpass indicated resources contain 6.7 billion lb Zn, 1.9 billion lb Pb and 43.5 Moz Ag.
- Additional Macpass inferred resources add 5.5 billion lb Zn, 2.2 billion lb Pb and 39.4 Moz Ag.
- Mactung indicated resources total 301.6 million kg WO₃, with a further 72.1 million kg inferred.
- Gayna project, ~180 km north of Macpass, has 3,800 m of initial drilling under analysis.
- Lundin Family Trusts now hold ~23% of Fireweed, signalling strong sponsor backing for long-lead northern infrastructure.
Our Take
JX Advanced Metals appears both here with Fireweed Metals and in our recent coverage of Lundin Mining’s move to 75% of the Caserones copper-molybdenum mine, signalling that JX is quietly consolidating long-life exposure to multiple critical metals streams across the Americas rather than single-asset bets.
With Macpass and Mactung carrying substantial zinc, lead, silver and WO₃ inventories in Canada’s North, Fireweed is positioning into the same ‘large, long-life base metals’ space that Lundin Group companies have targeted in Chilean copper (e.g. Caserones/Los Helados), which typically attracts patient capital but also demands robust logistics and power solutions.
The combination of US Department of Defense and Canada’s Critical Minerals Infrastructure Fund support around Mactung and Macpass suggests that tungsten and zinc from Yukon–NWT are being treated as strategic supply options, which could give Fireweed leverage in future offtake and infrastructure negotiations compared with non-subsidised peers in our database.
Prepared by collating external sources, AI-assisted tools, and Geomechanics.io’s proprietary mining database, then reviewed for technical accuracy & edited by our geotechnical team.
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