OZ Minerals lifted its production of gold and copper in the first three months of the year but costs were higher because of heavy rains.

Oz Minerals produced 27,182 tonnes of copper from its Prominent Hill mine in South Australia in the three months to March 31, up 1.4 per cent from the three months to December 31.

Gold production at Prominent Hill in the March quarter was 38,887 ounces, up 2.8 per cent from the December quarter.

The company said it remains on track to produce 100,000 to 110,000 tonnes of copper and 130,000 to 150,000 ounces of gold in calendar 2012.

The heaviest rain since operations began at Prominent Hill fell over three days at the end of February, restricting access to the mine’s main pit, OZ Minerals said.

The company drew on stockpiles as a result, increasing its costs, it said.

The stronger Australian dollar also contributed to higher costs.

Production came at a cash cost of 96.9 US cents a pound in the March quarter, up from 84.2 US cents in the December quarter, OZ Minerals said.

Overall costs remain within expectations, it said.

OZ Minerals shares closed flat on Thursday at $9.42.