Gold Fields and Gold Road Resources have increased their annual production forecast for the Gruyere gold joint venture project in Western Australia.
The JV partners, in an updated mine plan, have forecast the operation to produce an average of 300,000 ounces per annum, a 30,000 ounce increase on the project’s 2016 feasibility study.
Gruyere, which remains on target to produce first gold in the June 2019 quarter, has a 12-year mine life in the updated plan, down a year on the feasibility study.
The forecast increase in annual production has been driven by an “opportunistic purchase” of larger SAG and ball mills, lifting processing throughput from 7.5 million tonnes per annum to 8.2 million tonnes from 2021.
It also follows improvements to expected metallurgical recoveries and the addition of two deposits to the mine plan.
Gold Fields executive vice president Australasia Stuart Mathews said the JV had confidence to be able to provide the update to the life of mine plan with first gold remaining on target for the June 2019 quarter.
“The updated mine plan indicates an increase in annual average gold production to 300,000 ounces per annum. The update also provides more clarity around Gruyere’s all-in sustaining costs (AISC) and gold production forecasts,” Mathews said.
The JV’s average AISC over the life of the Gruyere mine are forecast at $1025 per ounce in the update.
Gruyere’s mine plan also reflects a new staged pit design that aims to provide lower risk delivery of ore to the operations processing facilities, while maintaining a similar grade and strip ratio profile.
Gold Road managing director Duncan Gibbs said the Gruyere project had been an incredible journey for the company since it was discovered in 2013.
“For Gold Road the updated mine plan means an attributable forecast share of approximately 150,000 ounces of gold on average over the 12-year mine life,” Gibbs said.
At the end of November, the overall project, and engineering, procurement and construction development was 85 per cent and 77 per cent complete respectively.