Two unions at Chile’s Centinela copper mine rejected further contract talks with Antofagasta Minerals on Wednesday and decided to strike after government-mediated negotiations failed to produce a deal.
The risk of a strike in Chile, the world’s largest copper producer, had been supporting global prices as output of the metal has been constrained by operational disruptions, natural events and declining ore grades.
The strike began at 8am local time (1100 GMT).
Union leaders said they wanted all workers to receive the same benefits regardless of union affiliation.
Antofagasta said it was “willing to continue discussions with their representatives in order to reach an agreement that takes into account the interests of both parties.”
“Despite the impacts typically associated with a strike, projected production remains unchanged,” it added in a statement.