Rimfire Pacific Mining (ASX:RIM) has reported initial metallurgical test results from its Murga Scandium Deposit indicate potential for atmospheric pressure extraction.
Fourteen‑day bottle roll tests on low‑iron scandium-mineralised material returned potential recoveries of 60%–90%, if extraction rates can be maintained over 100–250 days. The deposit hosts an inferred mineral resource estimate (MRE) of 11,900 tonnes of scandium oxide.
Rimfire has commenced two new bottle roll tests running over 160–180 days to build on the preliminary observations and provide more data on the suitability of atmospheric leaching.
“The initial test results are indicative and not definitive — we recognise the need to collect more data over a longer‑term period to confirm this, and the company has now commissioned further bottle roll tests,” Managing Director David Hutton says.
Murga is located adjacent to Sunrise Energy Metals’ (ASX:SRL) Syerston Scandium Deposit and Australian Mines’ (ASX:AUZ) Flemington Scandium Deposit within the Fifield District, approximately 70km northwest of Parkes in central New South Wales.
Murga’s scandium mineralisation contains approximately 16% iron, compared to other deposits in the district. Rio Tinto’s (ASX:RIO) Burra Scandium Deposit has a combined MRE iron grade of 34%.
Two 3.5kg composite samples of laterite and saprolite‑hosted low‑iron scandium-mineralised material from diamond drillhole FI2679 were subjected to bottle roll leaching at atmospheric pressures and ambient temperatures.
The tests were conducted by Simulus under the guidance of metallurgical process consultant Boyd Willis.
At completion of the 14 days, sufficient scandium had been recovered to indicate potential recoveries of 60%–90% if the same extraction rate was maintained over longer timeframes.
The rate of scandium recovery during the 14 days was relatively constant, and iron extraction was relatively low.
Depending on data from the stage two tests, Rimfire may undertake a column leach test to simulate a full‑scale heap leach or vat leach process.
The company will also conduct an agitated tank leach test at atmospheric pressures, higher acidity, and 95°C temperature concurrent with the stage two tests.
Rimfire Pacific Mining holds total scandium oxide resources of more than 16,000 tonnes across its Melrose, Currajong, and Murga deposits at Fifield.
Write to JC Villarba at Mining.com.au
Images: Rimfire Pacific Mining
