How Regis Resources’ Underground Ore Reserves at Tropicana Keep Defying Depletion

Continued Growth Amidst Depletion

Regis Resources has delivered another strong update on the Tropicana Joint Venture’s underground Ore Reserves, reinforcing the asset’s reputation as a world-class gold mine. As of 31 December 2025, the Tropicana JV reported total Mineral Resources of 5.4 million ounces and Ore Reserves of 1.9 million ounces, with underground Ore Reserves alone reaching 0.9 million ounces.

What stands out is the sustained growth in underground Ore Reserves, which have increased by over 500,000 ounces since 2021, despite ongoing depletion from mining activities. This trend highlights the JV’s effective exploration and resource conversion strategies, with underground Ore Reserves growing by 210,000 ounces net of depletion in 2025 alone.

Exploration Success Drives Confidence

The company’s exploration efforts continue to pay dividends, with drilling campaigns in 2025 enhancing confidence in down-plunge extensions of known mineralisation and uncovering new underground targets. Priority areas such as Boston Shaker, Havana, and the conceptual Cobbler target remain focal points, with drilling converting inferred resources into higher confidence categories.

These results underpin Regis’ optimism about Tropicana’s long-term production outlook, with the JV expecting strong cash flows well into the next decade. The underground Ore Reserve growth exceeding depletion by approximately 500,000 ounces since 2018 is a testament to the JV’s ability to replenish mined ounces and extend mine life.

Technical Rigor and Economic Viability

The update is supported by comprehensive JORC-compliant technical data, including detailed sampling, drilling, and resource estimation methodologies. The Ore Reserves are economically evaluated using conservative gold price assumptions of US$1,700 per ounce for Ore Reserves and US$2,000 per ounce for Mineral Resources, ensuring robustness in reporting.

Both open pit and underground mining methods are confirmed as technically feasible and economically viable, with established processing infrastructure and metallurgical recoveries around 87-89%. Environmental management and social licence considerations are also well addressed, reflecting responsible mining practices.

Looking Ahead

With a secure tenure extending to 2036 and a strong pipeline of exploration targets, Regis Resources is well positioned to continue growing the Tropicana asset. The ongoing conversion of inferred resources and discovery of new mineralisation zones will be critical to sustaining production and shareholder value.

Investors will be watching closely as further drilling results emerge and as the JV refines its mine plans to capitalise on these underground opportunities.