Mount Hope Metallurgy Shows +98% Gold Recovery at Mt Solitary

Exceptional Metallurgical Results De-risk Processing Pathway

Mount Hope Mining Limited (ASX:MHM) has delivered a strong vote of confidence in its Mt Solitary gold prospect with Phase 1 metallurgical testwork indicating a combined gold recovery exceeding 98%. Conducted by ALS Metallurgy in Tasmania, the tests confirm the gold is coarse, free-milling, and highly responsive to a conventional gravity and cyanidation (CIL) processing route. This outcome materially reduces metallurgical risk as the company pushes towards a maiden Mineral Resource Estimate.

The test composite, sourced from recent drilling, showed approximately 70% of gold recoverable by gravity concentration alone, with the remaining gravity tailings exhibiting 94.6% cyanide solubility. The gravity concentrate was upgraded to an impressive 9,890 g/t Au at 94% recovery from the coarse fraction, underscoring the deposit’s amenability to producing a high-grade product.

Coarse Free Gold and Medium Ore Hardness Support Low Complexity Processing

Optical and automated mineralogy confirmed native gold as the dominant gold-bearing phase, with visible free gold grains ranging up to 600 microns across all size fractions. The Bond ball mill work index of 13.1 kWh/t classifies the ore as medium hardness, indicating conventional, low-cost comminution is feasible.

Mount Hope’s Managing Director Fergus Kiley highlighted the significance: "These results confirm a clean, coarse-grained, free-milling gold system that responds exceptionally well to conventional gravity and cyanidation processing. The free-milling nature with no significant refractory behaviour supports a technically straightforward processing route." The findings build on the company’s May 2026 cyanide-solubility screening, which showed strong gold recovery potential in fresh rock at depth.

Historical Metallurgical Data Aligns with New Testwork

The Phase 1 results echo historical metallurgical studies conducted by Metcon Laboratories in 1999, which reported cyanide gold dissolution rates around 94% and gravity recoveries between 32% and 40%. While the historical gravity recoveries were lower, they were achieved without prior gravity concentration, suggesting the current combined gravity plus cyanidation approach offers improved recovery. The consistency between independent campaigns strengthens confidence in the deposit’s metallurgical characteristics.

Regional Processing Infrastructure Opens Development Options

Mt Solitary’s location within the Cobar Basin places it within reach of multiple operating CIL plants, including Manuka Resources’ Wonawinta plant (107km away), Aurelia Metals’ Peak plant (154km), and Kingston Resources’ Mineral Hill plant (195km). The demonstrated amenability to conventional processing aligns well with these nearby facilities, supporting potential low-capital development pathways such as toll treatment or ore sale arrangements.

Mount Hope is actively exploring these options as it advances the project. This strategic positioning could accelerate development timelines by leveraging existing infrastructure rather than committing to standalone processing facilities.

Next Steps Target Resource Definition and Process Validation

The company plans to expand metallurgical testing to cover variability across mineralisation styles and oxidation states, alongside further comminution characterisation to underpin process plant design. A scoping-level flowsheet development will build on the gravity plus CIL processing route indicated by current results.

Additionally, a Phase 3 drilling program is scheduled to extend geological understanding and support a maiden JORC-compliant Mineral Resource Estimate. The drill contract for this next phase was recently awarded, reflecting Mount Hope’s commitment to advancing Mt Solitary’s development potential.