Caledonia Mining Corporation Plc has increased underground measured and indicated mineral resources at the Blanket gold mine in Zimbabwe by 22% to 2.178 million ounces of gold, shifting its inventory past the previous 1.789 million-ounce total reported as of December 31, 2023.

The updated estimate, effective June 30, 2026, comprises 17.7 million tonnes at an average grade of 3.83 g/t. Measured resources grew 48% to 1.090 million ounces, while indicated resources rose 3% to 1.088 million ounces. Inferred resources declined 30% to 0.748 million ounces, which the company attributed to successful resource conversion rather than mining depletion alone.

Alongside the underground update, Caledonia declared a maiden surface mineral resource estimate at the operation, totaling 30,000 ounces of indicated gold and 14,000 ounces of inferred gold across oxide, transitional, and sulphide zones.

Chief Executive Officer Mark Learmonth linked the inventory expansion to prior capital allocation.

“Following the commissioning of the Central Shaft in 2021, Caledonia has used the increased operating capacity to re-start underground exploration, investing $3.733 million in deep drilling at Blanket over the last 6 years enabling the addition of 1.279 million ounces of measured and indicated ounces of gold (before depletion) - a discovery cost of $2.92 per ounce.”

— Mark Learmonth, Chief Executive Officer

The expanded resource base will serve as the foundation for upcoming operational milestones. Caledonia intends to file an NI 43-101 technical report on the estimates with SEDAR+ within 45 days, incorporating a restated Life of Mine Plan and a new mineral reserve estimate.

Additionally, a technical study evaluating options to deepen Blanket’s operations below the current depth of 1,100 metres is scheduled for publication toward the end of 2026.

Read the full announcement: Caledonia Mining Corporation Plc: Blanket Mine Underground Measured and Indicated Mineral Resources Estimate Increases by 22% to 2.18 Million Ounces and Declaration of a Surface Mineral Resource Estimate