Workers ended a 24-hour strike Thursday at Chile's Escondida Mine, the world's biggest privately owned copper mine, union officials said.
The miners walked off the job on Wednesday to press for payment of an annual bonus and changes in working conditions at the mine controlled by industry giant BHP Billiton.
Marcelo Tapia, president of the mine workers union, said the strike was observed by most of the 2,500 workers at the mine in northern Chile.
"We are awaiting the company's response, but if there is nothing we will take new measures," Tapia said.
The company has declined to comment on the strike, or its impact on production.
The last big strike at Escondida in July 2011 lasted 15 days, and cost nearly $400 million in losses.
The mine had earnings of $3.2 billion in 2012, up 14.2 percent from 2011.
It produced more than one million metric tons of copper last year.