PERTH (miningweekly.com) – Gold major Newcrest Mining on Monday reported that its gold production for the December quarter was flat, but that its copper production had increased.

The Australian mining company’s December quarter gold output declined to 614 715 oz, compared with 615 498 oz in the previous quarter and 620 691 oz in the prior year.

However, copper production increased to 25 176 t in the December quarter, from 23 723 t in the September quarter and 17 581 t a year earlier.

Newcrest’s gold production decreased as a result of planned lower production at the Cadia mine, in New South Wales, and the sale of its 50% interest in the Hidden Valley mine, in Papua New Guinea, to joint venture partner Harmony Gold.

The Cadia mine produced 179 173 oz of gold and 19 383 t of copper, compared with 195 301 oz of gold and 18 774 t of copper in the September quarter.

In the September quarter, the Hidden Valley mine contributed 10 520 oz of gold to Newcrest's production.

The gold production losses were offset by an increase in output at Lihir, in Papua New Guinea, and Gosowong, in Indonesia.

The Lihir operation delivered 227 498 oz of gold during the quarter, compared with 206 760 oz in the previous quarter. The Cadia mine, delivered 179 173 oz of gold and 19 383 t of copper, compared with 195 301 oz of gold and 18 774 t of copper, in the September quarter.

The Gosowong mine also delivered a production increase from 57 690 oz in the September quarter to 64 991 oz in the period under review.

The Telfer mine, in Western Australia, increased its gold and copper production to 111 277 oz of gold and 5 793 t of copper, from 110 225 oz of gold and 4 949 t of copper in the quarter immediately prior. However, the Côte d’Ivoire-based  Bonikro mine’s production decreased from 34 973 t to 31 775 oz of gold in the same period.

MD and CEO Sandeep Biswas reported that Newcrest had achieved a significant milestone in the December quarter, with Lihir reaching its target of an annualised mill throughput rate of 13-million tonnes, which was a record for the site.

He added that Cadia had continued to increase mill throughput, processing ore at an annualised rate of 26.4-million tonnes, a 6% increase on the prior quarter and above the nameplate capacity of the plant.

“These achievements and efforts by all our operations contributed to a 4.9% decrease in Newcrest’s all-in sustaining cost (AISC) per ounce, and an increase in production from our continuing operations.”

AISC reduced to $751/oz, from $790/oz in the September quarter.

For the full 2017, Newcrest maintained its production target of between 2.35-million and 2.6-million ounces of gold, and between 80 000 t and 90 000 t of copper.