FILE PHOTO: Sheets of copper cathode are seen at the

FILE PHOTO: Sheets of copper cathode are seen at the copper cathode plant inside the La Escondida copper mine near Antofagasta, some 1,545 km (980 miles) north of Santiago city and 3,100 meters (10,170 feet) above sea level, March 31, 2008.REUTERS/Ivan Alvarado/File Photo