Viking Mines reports a major metallurgical breakthrough at its Linka Tungsten Project, achieving a 62.5% WO3 concentrate at 59.8% recovery using combined gravity and flotation processing on a larger 10 kg sample, significantly improving previous results and validating a low-capex flowsheet ahead of maiden drilling.
- 62.5% WO3 concentrate at 59.8% recovery from 1.2% feed grade
- Testwork on larger 10 kg sample de-risks scale-up of gravity circuit
- Low-capex gravity-led flowsheet validated for premium concentrate
- Flotation optimization underway targeting >70% recovery
- Maiden drilling scheduled for June 2026 quarter
Step-Change Metallurgical Results at Linka
Viking Mines Limited (ASX:VKA) has reported a substantial leap in metallurgical testwork outcomes at its Linka Tungsten Project in Nevada. The combined gravity and cleaner flotation circuit has delivered a premium-grade concentrate containing 62.5% WO3 at a 59.8% recovery rate from a 1.2% WO3 feed grade. This represents a significant improvement over the 56.4% WO3 at 46.0% recovery reported in March, marking a meaningful step up in both grade and recovery.
Crucially, this latest testwork was conducted on a larger 10 kg sample, compared to the previous 2 kg batch, providing greater confidence in the scalability of the gravity circuit. The standalone gravity concentrate grade improved to 66.6% WO3 with a 42.7% recovery, underscoring the robustness of the flowsheet. Viking’s Managing Director Julian Woodcock highlighted the simplicity and low capital intensity of the process, which avoids complex chemical treatments common in critical minerals projects.
Gravity and Flotation Synergy Drives Recovery Gains
The testwork combined a refined gravity separation stage with a first-pass rougher and cleaner flotation circuit applied to the gravity tails. While gravity alone accounted for 42.7% recovery at 66.6% WO3, the flotation stages contributed an additional 17.1% recovery at 54.3% WO3 grade. Together, these processes raised the total recovery to nearly 60%, comfortably exceeding the >50% WO3 threshold required for saleable scheelite concentrate.
Ongoing optimisation of flotation reagents aims to push recovery beyond 70% while maintaining a premium concentrate grade. This work will be critical in finalising the processing flowsheet and refining the capital expenditure estimate in collaboration with Mineral Technologies. The low-capex, modular plant design enabled by gravity-led separation is expected to accelerate permitting and construction timelines, positioning Linka advantageously in the US tungsten supply chain.
Strategic Timing Amid Elevated Tungsten Prices
With ammonium paratungstate (APT) prices near all-time highs, US$3,050 per metric tonne unit CIF Rotterdam, Linka’s potential as a domestic US tungsten source gains strategic importance. The US Department of War and domestic manufacturers are actively seeking secure, NATO-grade tungsten supply outside traditional global channels. Viking’s progress in developing a premium concentrate with a low-cost processing pathway places it well within this critical supply chain.
These metallurgical advances come as Viking prepares for its maiden drilling campaign, scheduled for the June 2026 quarter, following regulatory approvals. The drilling aims to test historic high-grade zones and extensions across the Linka Project area, which includes multiple bulk samples currently undergoing variability testing. The company is also investigating ore sorting technology on recently collected stockpile samples, potentially accelerating near-term feed sources. This drilling and further metallurgical optimisation build on the company’s recent key permits for 63-hole drilling and new tungsten stockpiles identified announcements.
Next Steps in Process and Project Development
Viking’s metallurgical programme will now focus on flotation reagent optimisation, variability testing across multiple bulk samples, detailed comminution testing, and gravity separation enhancements at coarser grind sizes. Ore sorting trials on a ~40 kg sample are underway, potentially offering further processing efficiencies. Concurrently, the conceptual processing study with Mineral Technologies is advancing to finalise plant design and capital cost estimates.
Completion of a 3D geological model using digitised mapping and drillhole data will support drilling targeting and resource definition. The maiden drilling programme, now fully permitted, remains on track for the June quarter, a critical catalyst for validating resource potential and underpinning project economics.
Bottom Line?
Viking’s metallurgical strides at Linka validate a low-capex, scalable processing route that could fast-track US tungsten supply amid soaring prices, but flotation optimisation and drilling results will be pivotal next milestones.
Questions in the middle?
- How will flotation optimisation impact overall recovery and concentrate grade targets?
- Will maiden drilling confirm the continuity and scale of tungsten mineralisation suggested by metallurgical samples?
- Can ore sorting trials on stockpile material deliver near-term feedstock to accelerate project development?