On 8 October 2026, Rimfire Pacific Mining (ASX:RIM) reported results from Stage 2 long-term bottle roll leach testwork on low-iron scandium mineralised material from the Murga Scandium Deposit in central New South Wales. After 15 weeks, scandium recoveries reached 22.7% from saprolite and 15.2% from laterite.

Bottle roll results at 15 weeks

The two tests were run on a 0.74 kilogram saprolite sample and a 1 kilogram laterite sample, both composites of HQ quarter core from diamond drillhole FI2679, under atmospheric pressure and ambient temperature. Recoveries were 22.7% for saprolite and 15.2% for laterite at 15 weeks, with the bottle rolls continuing.

The tests build on earlier 14-day bottle roll results reported on 23 June 2026. Sulphuric acid consumption at 15 weeks was 0.34 tonnes per tonne for saprolite and 0.23 tonnes per tonne for laterite, which Rimfire described as low for atmospheric leaching.

The 52-week projection and its basis

Rimfire said that if the same rate of extraction were maintained over 52 weeks, recoveries of at least 60% for saprolite and at least 30% for laterite could potentially be achieved. The projection was derived by applying a linear line of best fit, excluding the initial rapid extraction, to weekly recovery data and extrapolating it.

The company justified the longer timeframe by noting that heap leaching of metallurgically analogous laterite nickel-cobalt-scandium deposits typically occurs over 100 to 400 days, and cited published research indicating that saprolite ores achieve 70% to 80% extractions over extended leaching periods.

Solution chemistry and laterite differences

The pregnant leach solution from saprolite had a scandium to iron ratio of 2.24 milligrams per gram at 15 weeks, which Rimfire said is high relative to atmospheric leaching of other scandium ores and may ease Downstream separation and purification. The company attributed lower laterite recoveries possibly to calcium, manganese and magnesium minerals consuming more acid.

Wider metallurgical study

The testwork is part of the Murga Scandium Metallurgical Study, which also includes column leach and agitated tank leach work, and will underpin a desktop financial study of atmospheric leaching of scandium from low-iron host rock. Murga has a Mineral Resource of 11.9 thousand tonnes of scandium oxide (reported 13 April 2026) and is adjacent to Sunrise Energy Metals’ Syerston deposit, about 70 kilometres north-west of Parkes.

Sector backdrop

Scandium is used in aluminium alloys and certain fuel cell designs, and few projects are in production. Atmospheric leaching is generally less Capital intensive than high-pressure acid leaching, but leach times and acid consumption determine its viability.

Bottle roll tests are small-scale laboratory tests, and results at that scale do not directly predict heap or tank recoveries.

Risks shareholders should weigh

The 60% and 30% recoveries are extrapolations from a linear trend and not measured results. The measured results at 15 weeks were 22.7% and 15.2%, and actual recoveries may be lower if the extraction rate declines over time.

The tests used small samples from one drillhole, and laterite recoveries are lower than saprolite. A 52-week leach time is long, and the commercial viability depends on column, tank and economic studies that are not yet complete.

Scandium Demand and pricing are less established than for larger commodities, and the project needs funding, approvals and a processing route. The company’s own financial study has not been completed.

What’s next

Rimfire expects to update on column leach tests by early November 2026, agitated tank leach tests by late November, and bottle roll results in early December 2026. These will feed a desktop financial study. Shareholders may wish to watch for those dates.