PERTH (miningweekly.com) – Gold miner Newcrest Mining has reported a quarter-on-quarter decline in gold and copper production – in line with its guidance provided at its 2013 year-end results in July.

Gold production declined 14% quarter-on-quarter to 586 573 oz, while copper production dropped 9% quarter-on-quarter to 19 632 t, owing to lower gold grades. However, on a year-on-year basis, the embattled group managed a 27% improvement in gold output during the September quarter and a 6% increase in copper production.

The company, which is getting a new CEO and chairperson, reported an all-in sustaining cash cost of A$1 093/oz, which was slightly below the average costs of A$1 001/oz during the 2013 financial year, which ended in June.

The miner said on Thursday that its Cadia Valley operation, in Australia, had increased its production by 10% over the quarter, to 154 232 oz of gold and 15 148 t of copper, as higher grades from Ridgeway were accessed and production increased from the Cadia East mine, displacing stockpile material as mill feed.

However, the Lihir operations, in Papua New Guinea, reported a 3% quarter-on-quarter decline in production reaching 194 713 oz of gold. Gold production was affected by planned lower gold grades and recoveries associated with the processing of more stockpile ore.

This was offset by increased mill throughput.

Newcrest said that the 18% increase in plant throughput at Lihir reflected the ongoing optimisation and improved reliability of the plant, associated with the refurbishment of the original plant and the commissioning of the flotation plant expansion, early in the quarter.

Meanwhile, the Telfer operation, also in Australia, reported a 24% decline in gold production, compared with the previous quarter, owing to a significant reduction in the average gold feed grade and a 9% reduction in mill throughput.

Gold production at Telfer reached 123 691 oz, while copper production was recorded at 4 485 t.

Newcrest told shareholders that the gold grade and mill throughput reflected an increase in the proportion of ore sourced from the openpit stockpiles during the quarter, owing to a disruption in the underground hoisting system.

The underground operation returned to planned production levels late in the quarter, following the repair of the hoisting system. A progressive reduction in openpit mining activities was planned for the remainder of the financial year.

At the Gosowong operation, in Indonesia, Newcrest delivered 71 227 oz of gold during the quarter, which was a 23% decline on the previous quarter. The decline was attributed to lower grade stopes in the underground orebodies.

The Bonikro project, in Cote d’Ivoire, delivered 17 784 oz of gold during the September quarter, which was 22% lower than the three months to June. Again, this decline was attributed to lower gold grade zones in the openpit mine.

Production at Bonikro was expected to increase over the remainder of the 2014 financial year, with higher grades.

The Hidden Valley mine, in which Newcrest holds a 50% interest, delivered a 7% increase in production, with gold reaching 24 926 oz along with 252 996 oz of silver.

The increased production was ascribed to a 10% increase in mill throughput and a 3% increase in gold recoveries. This was partly offset by a 2% reduction in gold grades.

Newcrest has maintained its production guidance of between 2-million and 2.3-million ounces of gold and between 75 000 t and 85 000 t of copper for the full year.