Copper extends gains on supply concerns

Copper futures climbed to a near two-month high above $4.82 per pound on Thursday, extending the prior session’s rally after Freeport-McMoRan declared force majeure on output from its Grasberg mine in Indonesia, the world’s second-largest copper source.

The decision followed a September 8 accident that killed two workers and left five missing after a massive mudflow of about 800,000 metric tons.

Freeport also cut its quarterly copper and gold sales guidance by 4% and 6%, respectively. The disruption underscores the market’s vulnerability to supply shocks, compounded by Hudbay Minerals’ suspension of operations at its Constancia mine in Peru due to protests.

Grasberg alone contributes 3.2% of global mined copper, nearly 30% of Freeport’s copper production and 70% of its gold output, highlighting the scale of the impact.

Prolonged curbs could drive prices higher and put additional strain on smelters.