Los Bronces miners down tools

Miners at one of Chile's largest copper operations walked off the job on Friday morning after rejecting the majority-owner's final offer in collective wage talks.

Over 1,700 workers at Anglo American's (LON:AAL) Los Bronces copper mine stopped work, after the union and the company failed to reach agreement despite a government-sponsored mediation process during contract negotiations. Anglo had reportedly offered workers a bonus of around $13,000 plus other benefits.

"The company regrets the rejection of an offer that it considers fair and responsible in the context of the current conditions of the mining industry in general and Los Bronces in particular," the London-listed mining major said in a statement.

Los Bronces is 50.1 percent owned by Anglo American; Chilean state miner Codelco and Japanese trading houses Mitsui & Co. and Mitsubishi Corp. also have stakes in the Anglo American Sur complex. Anglo's flagship mine is located high in the Andes mountains near Santiago. In 2015 it produced 437,800 tonnes of copper, or about 8 percent of the total output of Chile, the world's top copper producer, according to Reuters.

Los Bronces workers also went on strike in November 2014, but the issue at the time was working conditions.

Los Bronces is the second Chilean copper mine to be hit by labour unrest in recent days. Workers at Codelco's Salvador mine are also on strike, having failed to reach a wage agreement with their employer.

Salvador, which is the state-owned firm’s smallest operation and produced 49,000 tonnes of copper last year, has been battling to turn a profit after dwindling ore grades pushed up production costs, affecting a plan to extend the mine's life.

In August last year, the mine was hit by an around three-week strike by a different group of contract workers, which cost Codelco more than $15 million in lost production and damaged equipment.