Freeport McMoRan‘s Indonesian unit has resumed production of copper concentrate at its giant Grasberg mine, a spokesman told Reuters on Tuesday, ending a more than one-month stoppage.

“We have begun to resume operations in stages,” Freeport Indonesia spokesman Riza Pratama said, confirming that copper concentrate production had resumed on Tuesday.

Freeport stopped producing copper concentrate on Feb. 11 after Indonesia prevented it from exporting the material used to make refined copper, and its sole domestic buyer halted operations due to a strike.

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