Sunshine Silver weighs doubling mill capacity

AI desk brief

Sunshine Silver is designing a mill roughly twice the size assumed in its initial mine plan, lifting proposed throughput to 2,000 tonnes/day from 1,000 tonnes/day as it prepares a late-2028 restart at the Idaho silver mine. The larger plant would give the company room to expand output if drilling upgrades resources, but feasibility work in Q2 2027 must still prove the orebody can support the higher rate and define the extra capital needed.

The initial assessment had pegged capex at $286.9 million and average first-five-year silver output at 6.7 million oz/year over a 24-year mine life, though those figures do not cover the enlarged operation. Sunshine has already raised $310.5 million gross in its IPO, is dismantling the old mill, and is also studying a new antimony plant and restarting its silver-copper refinery, which has a 10 million oz/year nameplate capacity.