A view of the BHP Billiton’s Escondida, the world’s biggest copper mine, in northern Chile, in Antofagasta, Chile March 31, 2008. REUTERS/Ivan Alvarado/File Photo
A view of the BHP Billiton’s Escondida, the world’s biggest copper mine, in northern Chile, in Antofagasta, Chile March 31, 2008. REUTERS/Ivan Alvarado/File Photo