Gravity process successfully produced a 19x tungsten upgrade to stockpiled ore with further testing underway
HIGHLIGHTS
- Tungsten Concentrate Produced: Tungsten concentrates of 52.3% tungsten trioxide (WO3) were produced from preliminary gravity separation test work on large samples from tungsten-bearing stockpiles at the Johnson Creek mill site, sourced from the historical mining at the Golden Gate Tungsten mine, within Resolution’s Horse Heaven Antimony-Tungsten-Gold Project in Idaho, USA.
- Significant Tungsten Upgrade Achieved in Test Work: Stockpiled tungsten-bearing ore is clearly amenable to simple gravity flotation processing in preliminary test work, as indicated by a significant upgrade, by a factor of 19 (19 times), relative to the stockpile composite sample tungsten grades 1.85 wt% WO3, present predominantly as scheelite.
- Scoping Tests Completed: Heavy liquid separation (HLS) scoping tests have been completed, achieving up to 75.5% recovery, grading 52.3 wt% WO3, with an upgrade ratio of 19.
- Mineral Processing Test Work Progressing: Further testing of concentrates is underway with a larger sample (50kg) being prepared for concentration via shaker table, and final product results will be released in the coming weeks.
- Encouraging Results: Although the Heavy Liquid Separation (HLS) is preliminary, the results are encouraging for the short-term processing of the historical tungsten stockpile via simple gravity methods.
- Other Concentrate Test Work: Test work is also advancing on options to concentrate the antimony ore and gold at IMO labs in Perth, Australia, with further results soon.
- Smelting and Refining Discussions Progressing: Discussions with tungsten smelting and refining companies are underway.
- The processing options for tungsten stockpiles form part of Resolution’s broader Horse Heaven strategy, which includes recently acquired processing infrastructure and a major 2026 drilling program at Golden Gate starting in May, targeting gold and tungsten
The initial results are encouraging for the short-term processing of the historical tungsten stockpiles via simple gravity methods. This is a great start and I’m looking forward to discussing the final results in the coming weeks, while discussions are underway with smelters and refiners.
- RML's Senior Metallurgist, Adam Roper, PhD
WATCH:
RML’s CEO of US Operations, Craig Lindsay, gives an update on drilling preparations from the Horse Heaven Gold Antimony Tungsten Project.


