AFTER achieving record production of 211,690 ounces of gold at the Hidden Valley Gold Project during the financial year ending June 30, the Morobe Mining Joint Venture (MMJV) of Harmony Gold and Newcrest Mining recorded slightly lower production during the September quarter. The 9% decrease on the previous quarter to 27,286 ounces reflected a decrease in gold grade following access to above average grade ore in that period.
The decrease was partially offset by a 1% increase in recoveries. Silver production of 281,247 ounces was 40% higher than the previous quarter reflecting a 29% increase in grade, attributable to an increase in material from the Hidden Valley pit and a 5% increase in recoveries. Silver production for FY14 was 1,949,692 ounces.
All-in sustaining cost per ounce increased by 6% during the September 2014 quarter to Aus$1257 per ounce due to lower gold grades and higher fleet maintenance activity than the prior quarter. These factors were partially offset by an increase in silver by-product credits.
The FY14 production record exceeded the previous record of 201,464 set in 2011. The JV says the target was achievable through constant safe practices, delivery of production costs and reducing operation costs.
In an MMJV publication, Hidden Valley general manager Bevan Jones said that FY15 was shaping up to be even more challenging than FY14 with higher expectations in all areas. “We must ensure that we have a safe workplace free from harm where we can work productively. We also have increases in all physical production targets that will have to be closely tracked and effort put in every day to ensure that we meet them.
“FY15 will be an exciting year with major reinvestment through the purchase of a new mining fleet to help ensure that we are able to meet our increased production targets.”
MMJV has been drilling within the Hidden Valley Wau region, with the program designed to test potential high grade targets within the vicinity of the historic Wau mining centre.
Hidden Valley is an open pit gold and silver mine, consisting of three main lodes – Hidden Valley, Kaveroi and Hamata. Gold and silver doré produced at Hidden Valley is transported to the Perth Mint in Australia to be refined.
Construction of the mine began in 2007 and commercial production commenced in September 2010. The joint venture is continuing to ramp up operations to target annual production of 250,000 ounces of gold and 2.5 to 3 million ounces of silver. The mine sits within the New Guinea Mobile Belt which is one of the world’s pre-eminent geological terrains for porphyry copper-gold and epithermal gold mineralization.