CHILE Toronto-based FALCONBRIDGE is optimistic that inferred resources in the newly tested Rosario Oeste zone will eventually be added to the reserves of the Collahuasi copper mine. The inferred resources in the new zone stand at 248 million tonnes grading 1.54% Cu. Proven and probable reserves for the entire project are estimated to be 310.5 million tonnes grading 1.09% Cu, and there are probable reserves of 1.82 billion tonnes at 0.80% Cu. Reserves are sufficient for at least 50 years’ production at the world’s fourth largest copper mine.
The block of inferred resources lies in the centre of the Rosario Oeste zone, 300 metres from the proposed edge of the Rosario open pit. Copper mineralization is principally contained in a structurally controlled chalcocite supergene blanket that formed over a swarm of high sulphidation veins. The zone is open to the north, south and at depth. Currently, mining at Collahuasi is confined to the open pit in the Ujina orebody.
The main focus of exploration diamond drilling will continue to be the Rosario Oeste zone, but other targets on the property will also be tested.
The Collahuasi mine is a joint venture of Falconbridge (44%), ANGLO AMERICAN (44%) and a Japanese consortium led by MITSUI & CO. The project has an annual production of 465,000 tonnes of copper concentrate and 58,000 tonnes of copper cathodes. Go to www.Collahuasi.ci to view a satellite image of the northern Chilean Andes including the mine site.