- First quarter copper production falls seven per cent- Gold production down 10 per cent- Remains on track for full-year targetsChile-focused copper miner Antofagasta said production of copper, gold and molybdenum fell during the first quarter of its financial year but it remains on track to meet full-year targets.The UK-listed miner said first quarter copper production was 169,400 tonnes, down 7.4% from the previous quarter, as production was held back by scheduled maintenance at its Los Pelambres and Esperanza mines. Numis Securities forecast first quarter to be down slightly year-on-year at 177kt copper compared to 183kt in the final quarter.Gold production for the quarter was 56,800 ounces, a 10.3% decrease on the previous quarter as a result of lower production at Esperanza. Molybdenum production at Los Pelambres fell to 1,700 tonnes in the first quarter compared to 2,300 tonnes in the final quarter of 2013, mostly due to lower plant throughput and grade, it explained. The UK-listed miner said it remains on track to meet its full-year guidance of 700,000 tonnes of copper, 270,000 ounces of gold and 7,500 tonnes of molybdenum at a net cash cost of $1.45/lb. Cash costs before by-product credits in the first quarter were unchanged from the previous quarter at $1.83/lb. "Whilst production was lower during the current quarter as expected, cash costs were supported by the peso, which weakened by 6.8% against the US dollar compared with Q4 2013," Antofagasta said in its trading update. The second half of the year is expected to be stronger, with higher production and lower unit costs, than the first half.The miner, which is building another Chilean mine, Antucoya, expects it to start production next year.CJ