EditorialFILE PHOTO: Worker walks near the Congolese state mining company Gecamines' copper concentrator at its Kambove operation in the southern province of Katanga
EditorialFILE PHOTO: A worker from BHP Billiton's Escondida, the world's biggest copper mine, is pictured inside a copper cathodes plant in Antofagasta
EditorialFILE PHOTO: A train loaded with copper cathodes travels along a rail line inside the Chuquicamata copper mine, which is owned by Chile's state-run copper producer Codelco