A view of the Cerro Rico mine (background) is seen in Potosi, some 600 km (373 miles) south of La Paz, in this March 2003 file photo. High silver prices are drawing a frenzy of miners to a colonial-era mine at Potosi in Bolivia, but the mine has become so dangerous that authorities fear the mine, part of a World Heritage Site, could collapse. Picture taken March 2003. To match feature: BOLIVIA-MINING/POTOSI
REUTERS/DAVID MERCADO