OZ Minerals (OZL) has posted a fall in first-quarter copper production, but has come in well ahead of market expectations, as it reported productivity improvement measures at its Prominent Hill mine.
Investors were impressed, sending the miner's shares 5.87% higher to $3.97 at 10.55am (AEST), against a benchmark index lift of 0.64%.
The result is well ahead of Bloomberg analyst forecasts, which had tipped quarterly copper production of 15,400 tonnes.
In the three months to March 31, OZ Minerals produced 18,182 tonnes of copper, down from 20,474 tonnes in the previous corresponding period.
The miner produced 33,792 ounces of gold in the March quarter, up from 31,790 ounces in the previous corresponding period.
OZ Minerals reported cash costs of $US1.22 ($A1.30) per pound, down from the $US1.85 per pound it posted in the March 2013 quarter.
The miner attributed the fall in cash costs to improved productivity, lower expenditure and reduced waste mining volumes.
OZ Minerals is also continuing to undertake a pre-feasibility study for the Carrapateena project, with work on the mine design largely completed during the quarter.
The pre-feasibility study will be ready for internal review before the end of the first half of 2014, the miner said.
OZ Minerals said it is still developing its Malu Underground mine, with first production expected in late 2014.
Drilling on projects in Jamaica and Chile has also commenced.
The miner provided no update on guidance in its March quarter update.
In January, OZ Minerals said it expected to produce 75,000 tonnes to 80,000 tonnes of copper and 130,000 ounces to 140,000 ounces of gold in 2014.