Rio Tinto Q3 refined copper output up 30 pct

SYDNEY, Oct 17 - Rio Tinto Ltd/Plc reported a 30 percent rise in third-quarter refined copper production over the same period a year earlier as it moved to capture more of a global boom in mineral demand. But it said on Wednesday that mined copper output fell 6 percent in the third quarter compared to the same period the previous year because of less rich ore grades, sending its stock down more than 3 percent. Aluminium production was flat during the quarter, the company said. Copper is a key component underpinning profit forecasts for the Sydney and London-listed company, accounting for nearly half of first-half profits. Iron ore was a distant second at 29 percent of first half earnings, with aluminium providing 11 percent of earings during the period. Rio's 30 percent stake in the Escondida copper mine in Chile, the world's biggest, delivered 101,200 tonnes of contained copper and 16,100 tonnes of refined cathode. Aluminium output was set to soar in 2008 to more than 4 million tonnes when Rio completes its $38.1 billion acquisition of Canadian producer Alcan Ltd AL.NAL.TO to assemble the world's largest aluminium company. Rio said its iron ore production and shipments in the third quarter were near record levels, with output in Australia 11 percent ahead of 2006 for the first nine months of the year. Congested shipping ports and railways in eastern Australia hurt third-quarter coal production, reducing hard coking coal output 10 percent and thermal coal production 24 percent. Rio shares were down 3.5 percent at A$109.50, outrunning losses of 0.5 percent in the S&P/ASX200.