Resolution Minerals Produces 52.3% WO3 Tungsten Concentrate with 19x Upgrade

High-Grade Tungsten Concentrate from Historical Stockpiles

Resolution Minerals Ltd (ASX:RML) has reported a significant metallurgical milestone by producing tungsten concentrates grading 52.3% tungsten trioxide (WO3) from gravity separation test work on stockpiled ore at the Johnson Creek mill site in Idaho, USA. This material, sourced from historical mining at the Golden Gate Tungsten mine, underwent preliminary heavy liquid separation (HLS) tests that achieved an impressive 19 times upgrade from the original 1.85% WO3 grade in the stockpiles.

The gravity separation process yielded up to 75.5% recovery of tungsten, confirming the amenability of the stockpiled ore to simple and cost-effective processing methods. These results are particularly encouraging given the preliminary nature of the test work and the composite nature of the samples.

Particle Size Influences Concentrate Quality and Recovery

Detailed size-by-assay testing revealed that decreasing particle size enhances both the grade and recovery of tungsten-bearing minerals, predominantly scheelite, in the ore. Samples crushed to pass 3.35mm and screened into seven size fractions demonstrated that the finest fractions, especially those between 0.053mm and 0.02mm, delivered the highest concentrate grades and recoveries.

Further metallurgical work is underway on a larger 50kg sample ground to below 0.25mm, to be concentrated using a shaker table. The final product results from this next phase of testing are expected in the coming weeks, which will provide a clearer indication of the commercial viability of processing these stockpiles.

Integration with Broader Horse Heaven Project Strategy

This tungsten processing breakthrough fits into Resolution’s broader strategy at the Horse Heaven Antimony-Tungsten-Gold Project, which includes recently acquired processing infrastructure and a major drilling campaign scheduled to commence in May 2026. The upcoming Phase 2 drilling program, targeting up to 13,700 metres at Golden Gate, aims to define the scale of gold and tungsten mineralisation and support a maiden Mineral Resource Estimate.

Alongside tungsten, test work on antimony and gold concentrates is progressing at IMO labs in Perth, with results anticipated soon. Concurrently, Resolution is advancing discussions with tungsten smelting and refining companies to explore downstream processing options, a critical step for eventual commercialisation.

Resolution’s efforts to fast-track its US critical minerals projects were recently bolstered by a A$20 million institutional placement to accelerate exploration and development, as well as the company’s preparation for a NASDAQ listing to enhance its US market presence. These moves align with the strategic importance of domestic critical minerals supply, underscored by the FAST-41 permitting status granted for Antimony Ridge, part of the Horse Heaven Project. The FAST-41 designation aims to expedite permitting processes for projects critical to US national security and industrial needs, including tungsten and antimony supply chains.

Resolution’s tungsten stockpile processing results complement this momentum, highlighting the potential for near-term production from existing resources while the company advances its exploration and resource definition programs. The Golden Gate mine’s historical significance, having contributed substantially to US tungsten supply during World War II, adds further weight to the project’s strategic value.

Towards Resource Definition and Commercialisation

While the initial metallurgical results are promising, the company acknowledges that further detailed sampling and volume surveys of the stockpiles are required to comply with JORC reporting standards and to better quantify the resource. The composite nature of the samples and variability within the stockpiles mean that grade continuity and tonnage estimates remain preliminary.

Resolution’s in-house Senior Metallurgist, Dr. Adam Roper, emphasised the encouraging nature of the results for short-term processing via simple gravity methods and highlighted ongoing discussions with smelters and refiners as critical next steps. The company’s planned drilling program and continued metallurgical testing will be key to advancing the project towards a defined resource and eventual production.

This announcement builds on Resolution’s recent capital raise and strategic initiatives to fast-track its US projects, including the A$20 million placement and the FAST-41 permitting status for Antimony Ridge, positioning the company well within the critical minerals sector.