Cost pressures 'returning' to aluminium sector, Rio Tinto warns

Rio Tinto's aluminium output rose 4% in the third quarter against a return of cost pressures in the industry.

The miner's share of aluminium production reached 962,000 tonnes, up 4% quarter-on-quarter and 2% higher year-on-year, driven by a resumption of normal production at Laterriere after a transformer failure.

"Cost pressures are returning to the aluminium industry, including the effect of stronger currencies, and the higher costs of caustic, coke and pitch," Rio Tinto said.

However, the miner is keeping its full-year output forecast unchanged at 3.9 million tonnes.

Meanwhile, an increase in third-party demand helped bauxite production rise to 9.2 million tonnes in the quarter, up 5% from the previous three months and 7% higher year-on-year.

Alumina production was at 2.2 million tonnes, unchanged from the second quarter and down 5% year-on-year.

For the full year, Rio Tinto expects to produce 35.8 million tonnes of bauxite and 9.2 million tonnes of alumina, 2% lower than its early forecasts.