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BHP and Rio spend $4.5bn on mine
BHP Billiton and Rio Tinto have approved plans for a $4.5bn (£2.8bn) expansion of the Escondida mine in Chile, the world’s biggest copper mine, where BHP said this morning the ore reserve estimate has been increased by 25 per cent. BHP, operator of the mine, plans to spend $2.6bn on two projects to boost output at the mine, while Rio’s share of the projects is $1.4bn. The projects are designed to give the partners access to higher ore grades, with a new concentrator plant and mineral handling system that will boost production to more than 1.3m tonnes a year by June 2015.