Copper prices are tumbling as miners in the top producing nation gird to fight for bigger bonuses, setting the stage for labor strife that raises the risk of supply disruptions.

The government established a commission to ensure company is complying with its contractual obligations regarding the giant copper and cobalt project.

Companies including First Quantum Minerals and EMR Capital are ready to raise funding for the projects.

A ruling in January by Chile's Supreme Court upheld local indigenous communities' complaint.

Newcrest expects to begin the early works program for the expansion by the end of this year.

Wyloo said it is considering making a "superior" offer to acquire the remaining stake in the Canadian nickel miner.

Mining stocks also slid, with BHP down more than 18% from the previous week, Freeport-McMoRan down 16%, and Glencore down 12%.

The company expects to end the year with production of 2.3-2.35 million ounces of gold with no change to the production guidance.