KoTH Ore Reserve Grows to 2.2M Ounces; Processing Capacity to Hit 7.5mtpa by FY27

Ore Reserve Growth and Mine Life Extension

Vault Minerals Limited (ASX: VAU) has announced a significant update to its Leonora operating strategy, anchored by a 33% increase in the King of the Hills (KoTH) open pit Ore Reserve. The new reserve stands at 110 million tonnes grading 0.62 grams per tonne gold, equating to 2.2 million ounces. This expansion underpins an extended mine life of 18 years, reflecting the scalability of the KoTH mineralised system and the company's confidence in its flagship asset.

The increase in Ore Reserve is largely driven by recent drilling success and a strategic lowering of the cutoff grade to 0.23 g/t, supported by a constructive medium to long-term gold price outlook. The expanded reserve provides valuable operational flexibility, with mining stages scheduled to commence waste stripping as late as FY32, allowing Vault to adapt to market conditions.

Processing Plant Upgrades to Boost Capacity and Efficiency

Complementing the reserve growth, Vault is advancing its Stage 2 processing plant upgrade at KoTH, which will dovetail with the ongoing Stage 1 upgrade. Together, these enhancements will increase processing throughput by 50%, from the current capacity to 7.5 million tonnes per annum by late Q2 FY27. The Stage 2 upgrade, budgeted at approximately $92 million, includes the installation of a 9MW regrind ball mill, upgraded gravity and carbon recovery circuits, and a new tailings thickener, all designed to increase metallurgical recovery and reduce unit costs.

Stage 1 works are well underway, with significant civil progress including crusher vault excavation and tank footings. The combined capital investment for both stages totals around $172 million, with expenditures spread across FY25 to H1 FY27. Importantly, Vault plans to fund these upgrades internally, leveraging growing free cash flow as hedging volumes step down and the hedge book is extinguished by early FY27.

Production Outlook and Operational Strategy

Vault projects average annual gold production of 215,000 ounces over the next five years, peaking at 235,000 ounces following the Stage 2 upgrade completion. This production profile is supported by a blend of 75% Ore Reserves and 25% Inferred Mineral Resources, the latter carrying inherent geological uncertainty. Recent underground drilling at KoTH and the nearby Darlot mine has increased confidence in life-of-mine extensions, with potential for further resource conversion.

Mining rates at KoTH are expected to rise by approximately 35%, with average annual material movement of around 14 million bank cubic metres. Vault is evaluating options for mining fleet upgrades or contract changes to support this increased scale, aligned with the expiry of the current mining contract in December 2026.

Environmental and Regulatory Considerations

The KoTH project benefits from established infrastructure and environmental approvals for current operations. Amendments to the Mining Proposal, Closure Plan, and Works Approval will be required to accommodate the processing plant upgrades and expanded mine footprint. Vault anticipates securing these approvals in a timely manner, given the project's operational status and prior regulatory experience.

Overall, Vault Minerals’ announcement reflects a robust growth trajectory for its Leonora operations, combining resource expansion, capital investment, and operational optimisation to enhance its competitive position in the prolific Leonora gold district.