Successful Initial Test Work Shows Nearly Complete Recovery Of Stibnite (Antimony Sulphides) From Lower Grade Samples
HIGHLIGHTS
- High Antimony Recovery: High rates of antimony recoveries in sulphides have been reported from concentrate test work on Antimony Ridge samples. Rougher flotation tests for stibnite were performed at IMO labs in Perth, Australia. High sulphur recovery of 99.5% indicates nearly complete recovery of the stibnite from the sample in this rougher concentration stage.
- Solid Results from Lower Grade Samples: The high sulphide recoveries were achieved from lower grade samples containing ~10% Antimony. This is an encouraging indication for potential future operations because potentially all stibnite may be recovered, even if high-grade antimony were to be diluted by surrounding waste or gangue material during extraction.
- Further Antimony Concentration Test Work Underway: Further concentration stages are underway in test work on Antimony Ridge samples. The “rougher” flotation work is aimed at high recovery of antimony. The following “cleaner” stages are designed to take the “rougher” sulphide concentrate and focus on achieving high grades, targeting an increase in grade from ~30% to >50% Antimony.
- Excellent Support for Prior Antimony Trioxide Results: The high rates of antimony recovery in concentrates are excellent support for the previously reported 99.38 wt.% Antimony Trioxide product produced from large samples of stibnite from the Antimony Ridge historical open pits, using the conventional pyrometallurgical process of volatilisation (ASX announcement 14 April 2026).
- Numerous Vein Swarms: 3D modelling of numerous known antimony and silver-bearing veins, vein swarms and stockworks, over a large area (1,000m x 700m) (170 acres), has revealed significant size and expanding scale potential at Antimony Ridge (ASX announcement 10 April 2026).
- FAST-41: Horse Heaven was selected for the U.S. FAST-41 Transparency Coverage by the US-based Permitting Council, expected to accelerate permitting timelines with an application for 250 drill holes and large-scale bulk sampling (ASX announcement: 8 April 2026).
- Antimony Ridge forms part of Resolution’s broader Horse Heaven strategy, which includes recently acquired processing infrastructure, tungsten stockpiles and a major 2026 drilling program at Golden Gate starting on 7 May of up to 13,700m of diamond core drilling planned.
The initial concentration results from the rougher flotation test work are very encouraging for Antimony Ridge samples. Capturing virtually all the antimony sulphides is an excellent sign of a simple and robust processing flowsheet for antimony. I’m looking forward to discussing further results in the coming weeks.
WATCH: RML’s CEO of US Operations, Craig Lindsay, gives an update on the tungsten stockpiles at the Horse Heaven Gold Antimony Tungsten Project.
