Highlights

  • Heap leach column testwork on Mulgabbie North paleochannel material recovered 95 per cent of the gold.
  • Recovery passed 60 per cent in 15 days and 90 per cent in 65 days, finishing at 95 per cent.
  • Hole MNODH 022 intersected 6 metres at 11.64 g/t gold from 22 metres, including 1 metre at 61.10 g/t.
  • The project's 2023 resource totals 11.638 million tonnes at 0.70 g/t gold for 260,000 ounces.

Ninety-five per cent of the gold came out. OzAurum Resources Limited (ASX:OZM) said on 28 October 2026 that heap leach column testwork on material from its Mulgabbie North Gold Project, about 130 kilometres north-east of Kalgoorlie in Western Australia, recovered 95 per cent of the gold. The company said the result supports a heap leach route as a lower-capital alternative to a conventional carbon-in-leach plant, while cautioning that laboratory column results are not necessarily indicative of recoveries at operating scale.

The testwork

Column 3 was composited from paleochannel material at 21 to 29 metres downhole in metallurgical diamond hole MNODH 022, crushed to minus 12 millimetres, with a head grade of 2.58 grams per tonne gold. Recovery exceeded 60 per cent in 15 days and 80 per cent in 35 days, reached 90 per cent at 65 days and finished at 95 per cent. Columns across three ore types all returned what the company described as excellent recoveries.

Cyanide consumption was about 0.26 kilograms per tonne, which the company said may be lower in field application and compares with about 0.5 kilograms per tonne it described as normal. The work was done at ALS Balcatta in 150-millimetre PVC columns, leached at 10 litres per square metre per hour, with liquor sampled every 48 hours.

The company called the tests indicative and preliminary. Fresh-rock results from other projects, including Binduli and Apollo Hill, are cited for context only, and there is no certainty of similar results at Mulgabbie North.

The drill intercept and resource

Alongside the metallurgy, hole MNODH 022 intersected 6 metres at 11.64 grams per tonne gold from 22 metres, including 1 metre at 61.10 grams per tonne.

The project's Mineral Resource Estimate, reported on 18 July 2023 under JORC 2012 at a 0.30 gram per tonne cut-off to 150 metres depth, totals 11.638 million tonnes at 0.70 grams per tonne for 260,000 ounces. That comprises 39,000 ounces Measured, 128,000 Indicated and 93,000 Inferred. Fresh material makes up 184,000 ounces, about 71 per cent. The company said no new information materially affects the estimate.

Geology and tenure

Mineralisation sits in the Relief Shear, a corridor up to 50 metres wide that extends about 8 kilometres within the company's tenure, with high-grade gold concentrated where faults intersect the shear. Northern Star's Carosue Dam operations are about 2 kilometres away.

The project covers mining lease M28/240, prospecting licences P28/1356 and P28/1357 and exploration licence E31/1085, which the company describes as in good standing. A 2 per cent net smelter royalty applies on M28/364 once production exceeds 100,000 ounces of gold.

What comes next

The company said the results support a Stage 1 development and a possible Stage 2 expansion along the Relief Shear corridor. Heap leach testwork now moves to fresh material, which OzAurum identified as the main growth lever beyond Stage 1. More diamond and reverse circulation drilling is planned, including testing mineralisation that remains open at depth.

The announcement gives no capital cost estimates, development timetable or financing plan, and references no mining study. No audits or reviews of the sampling techniques and data have been undertaken, so the recovery figure is a laboratory result on a single composite rather than evidence of project economics.