Last month, members of Congress wrote urging the Department of Defense to prioritize planning for seabed mining as a "new vector of competition."

This new period of validity for the mining concession is now until 2049.

Through the newly formed Minera El Encierro, the companies will carry out exploration for five years in a property comprising 35 concessions.

The miners' union expressed concern about the construction workers' plans to force their way into the mine on Jan. 9.

Production was down 16% at Codelco, while it jumped 6.3% at Escondida and rose 2.8% in Collahuasi.

Chief executive Mark Bristow approached some of First Quantum’s largest investors late last year, according to Bloomberg sources.

Teck has a first option to earn a 55% interest over three years, and the two companies will form a joint venture thereafter.