Highlights

  • Rose Hill’s maiden underground Ore Reserve totals 31,600 ounces of gold.
  • The 30 June 2026 Mineral Resource contains 94,000 ounces.
  • The reserve scenario indicates approximately AUD 24.5 million free cash flow.
  • Additional feasibility and geotechnical work is required before development.

Maritana Minerals lodged an amended version of its Rose Hill Mineral Resource and maiden Ore Reserve update with the ASX on the evening of 3 November 2026. The document replaces the original announcement released on 31 August 2026, which first declared the reserve. (ASX:MRT)

The amendment corrected the named Competent Person for the Mineral Resource and related disclosures. The amended version names Stephen Godfrey instead and corrects minor drafting errors. Maritana said there were no changes to the reported Mineral Resources or Ore Reserves. (ASX:MRT)

The maiden Ore Reserve for the Rose Hill Underground totals 420,000 tonnes at 2.34 grams per tonne gold for 31,600 ounces. Of this, 70,000t at 2.14g/t is classified as Proved and 350,000t at 2.37g/t as Probable. The reserve uses a 1.3g/t cut-off and a gold price assumption of AUD 4,500 an ounce.

It is underpinned by a Mineral Resource, stated as at 30 June 2026, of 0.81Mt at 3.61g/t gold for 94,000 ounces. That comprises an open pit component of 287,000t at 1.99g/t for 18,000 ounces at a 0.5g/t cut-off, and an underground component of 524,000t at 4.49g/t for 76,000 ounces at a 1.0g/t cut-off, re-reported from 2.0g/t. An Inferred portion of 194,000t at 4.53g/t for 28,000 ounces was excluded from the reserve, and the company described it as potential upside at depth.

Underground Mining and Black Swan Processing

Rose Hill lies about 0.5km southeast of Coolgardie and 35km west of Kalgoorlie-Boulder in the Western Australian Goldfields, on ground with a mining history dating to 1893.

The reserve is supported by a pre-feasibility study (PFS) completed in July 2026. The planned mining method is top-down long hole open stoping with pillars on 25m level spacing, at a scheduled rate of 270,000 tonnes a year. Ore would be hauled about 85km to the Black Swan processing facility, where the plant is being converted to gold processing through a carbon-in-leach circuit. Black Swan has capacity of up to 2.2Mtpa and is planned to operate initially at 1.5Mtpa.

The PFS applies a processing recovery of 91 per cent, while its base case uses an overall recovery of 78 per cent that allows for unplanned losses.

Economics, Qualifications and Next Steps

For the Ore Reserve scenario, the company estimated free Cash Flow of about AUD 24.5 million over a mine life of around 26 months, against total costs of about AUD 104.8 million. Those costs include roughly AUD 75.5 million in project mining costs and AUD 4.3 million in Capital purchases.

A broader life-of-mine design that includes Inferred material extends to about 41 months, but Maritana stated that it is not a production target. Life-of-mine figures referenced from scoping studies released on 17 February 2026 are preliminary and, the company noted, are not sufficient to support Ore Reserve estimates.

The company is targeting first gold from Black Swan in the second half of calendar 2027. Before development proceeds, the PFS recommends further geotechnical drilling of about eight to 16 holes, hydrogeological work and a full feasibility study. Maritana also sees scope to expand the resource through additional drilling at depth.

Key Insights

The Rose Hill reserve gives Maritana Minerals (ASX:MRT) a defined underground mining case, although the short reserve life and remaining study requirements limit conclusions about future production. The amended release did not change the reported resource or reserve estimates.