Rimfire Pacific Mining Triples Murga Scandium Resource with Low-Iron Extraction Potential

Murga Resource Expansion Triples Scandium Inventory

Rimfire Pacific Mining (ASX:RIM) has dramatically expanded its Murga Scandium Deposit in New South Wales, announcing a 300% increase in its inferred mineral resource estimate to 56.1 million tonnes grading 138ppm scandium (Sc). This translates to 7,760 tonnes of contained scandium metal, or 11,900 tonnes of scandium oxide, positioning Murga as a cornerstone asset within Rimfire’s Fifield project.

The upgrade, prepared by H&S Consultants and reported under the 2012 JORC Code, replaces previous smaller estimates and reflects successful 2025 drilling campaigns that tested peripheral ultramafic zones. Significantly, the resource remains open both laterally and potentially at depth, with multiple mineralised zones identified over a 15km² area, underscoring substantial upside.

Low Iron Content Could Unlock Cheaper Processing

What sets Murga apart in the Fifield scandium district is its relatively low iron content; approximately 16% Fe compared to up to 34% Fe in nearby deposits like Rio Tinto’s Burra. This geochemical profile raises the prospect of extracting scandium via atmospheric leaching (AL), a less capital-intensive and simpler process than the high-pressure acid leaching (HPAL) currently under consideration for other local deposits.

Rimfire is moving quickly to confirm this potential, with metallurgical test work scheduled under the guidance of process consultant Boyd Willis. The company is finalising laboratory quotes for tests aimed at establishing scandium recoveries from Murga mineralisation, a critical step before progressing toward economic studies.

Follow-Up Drilling and Metallurgical Testing Planned for June Quarter

With regulatory approvals underway, Rimfire aims to commence follow-up drilling in the June 2026 quarter. The planned program includes exploration drilling on 100m by 100m spacings to extend the resource and infill drilling on 50m by 50m spacings in higher-grade zones to potentially increase the grade and contained metal. Additionally, investigations into anomalous scandium found in underlying fresh ultramafic basement rocks will seek to identify new mineralised zones.

Rimfire’s Managing Director David Hutton emphasised the iterative nature of resource definition at Murga, noting that “quantifying such a large and geologically variable greenfields area is never a linear process.” He highlighted the company’s confidence in growing its global scandium inventory, which now stands at 10.6 kilotonnes of scandium metal (16.2 kilotonnes of scandium oxide) across the Fifield district, including the Malamute prospect at Rabbit Trap, located some 40 kilometres north of Murga.

This recent resource growth builds on Rimfire’s strategic consolidation of the Rabbit Trap Scandium Project, where strong drilling results at Malamute have confirmed significant scandium mineralisation over a broad area, as detailed in the company’s full control acquisition of Rabbit Trap. This regional synergy enhances Rimfire’s position as a leading scandium developer in Australia’s emerging critical minerals landscape.

Robust Technical Foundations Underpin Resource Confidence

The resource update is supported by a comprehensive dataset comprising 281 drill holes totalling over 7,500 metres, including diamond core, reverse circulation, and aircore drilling. Sampling and assay protocols adhered to industry standards, with quality control measures including certified reference materials and field duplicates ensuring data integrity.

Geostatistical analysis employed Ordinary Kriging estimation within mineralised wireframes, with grade continuity moderately defined and a nominal scandium cut-off grade of 100ppm applied. The inferred classification reflects the current drill spacing and geological understanding, with plans to upgrade confidence through infill drilling.

Density data was extrapolated from the nearby Melrose deposit, and while metallurgical test work on Murga is pending, previous acid-leach tests on Melrose laterite material demonstrated scandium recoveries exceeding 90%, lending optimism to processing prospects.

Environmental and Operational Considerations

Murga is situated on private freehold land used primarily for grazing and cropping, with no native title claims. The terrain is flat semi-arid, favourable for open pit mining and infrastructure development. Rimfire envisages a conventional shallow open pit operation with truck and shovel methods, potentially free digging the overburden and mineralised laterite.

Environmental assumptions include sealed acid leaching tanks and neutralisation of spent acid, with groundwater naturally saline and requiring management. The presence of low levels of pyrite indicates the need for acid mine drainage containment programs.