Deep-vein wolframite, 400 m below surface
Scheelite and wolframite occur in high-temperature hydrothermal veins where tungsten-bearing fluids intruded Precambrian granite. The deposit carries a 0.62% WO₃ head grade — above the 0.45% threshold for economic underground extraction.
Pre-disturbance baseline
Twelve months of ecological baseline surveys — boreal songbird nesting density, lichen coverage, groundwater chemistry — documented before the first drill hole.
Cut-and-fill stoping, zero surface subsidence
Long-hole stoping with paste backfill returns cemented tailings underground, eliminating surface impoundment risk and restoring pillar strength. Ore is hoisted at 1,200 tonnes per day through a single-compartment shaft.
Zero-discharge underground
Mine water is captured, treated through a closed-loop system, and reinjected. Surface water quality at the monitoring station downstream has remained within background limits for six consecutive years.
Gravity separation + froth flotation
Run-of-mine ore passes through jaw crushing, ball milling, and a two-stage gravity circuit achieving 72% WO₃ recovery. Flotation polishing brings wolframite concentrate to 65% WO₃ for hydrometallurgical feed.
Water recycling circuit
Process water is recovered at 94% through a thickener-and-clarifier loop. Fresh water draw from the watershed is 0.18 m³ per tonne of ore processed — 38% below the industry average.
APT synthesis → powder metallurgy
Concentrate is digested in sodium hydroxide, precipitated as ammonium paratungstate, and calcined to tungsten trioxide. Hydrogen reduction yields metal powder at 99.97–99.99% purity, graded by Fisher Sub-Sieve particle size for each end-use specification.
Energy decarbonization
The refinery runs on a 14 MW hydroelectric power purchase agreement signed through 2035. Scope 1 emissions from the refining circuit are 0.8 kg CO₂e per kilogram of metal produced.
Penetrators, filaments, carbide — delivered
Finished product ships as: (1) pressed-and-sintered billets for kinetic energy penetrators, (2) 0.6–3.5 µm powder for cemented carbide tooling, (3) drawn wire for semiconductor furnace components, and (4) high-density alloy ingot for radiation shielding and counterweights.
Canopy restoration
The reclamation fund has replanted 340 hectares of boreal canopy on legacy disturbance, using locally-sourced Picea glauca and Betula papyrifera stock. Monitoring confirms 78% seedling survival at year three.