OZ Minerals has extended the mine-life at the South Australia Prominent Hill iron-oxide copper-gold mine until 2029.
The extension was made possible by achieving an 18% growth in underground ore reserve to 39Mt at 1.7% copper equivalent.
The increase in ore reserve allows the company to achieve an underground production rate of 3.5Mtpa-4Mtpa from 2019 until 2029.
OZ Minerals managing director and CEO Andrew Cole said: “Prominent Hill continues to develop its pedigree as a strongly performing, long-life asset, with underground Reserve life-extending as the open-pit draws to a close.
“Our aim is to continue extending Prominent Hill underground mine-life year-on-year. An estimated 80Mt of underground Resource has not been converted to Reserve, so there is significant potential for further extensions as we move forward.
“Stockpile processing will maintain the plant at full capacity to 2023, and with open-pit related costs already incurred, we are expecting substantial value to be realised through this period.”
The company noted that the underground ore reserve for copper and gold metal has increased by 13% and 27% respectively.
Furthermore, OZ Minerals increased stockpiles by around 35% to 27Mt.
Upon completion of the open-pit closure in the first quarter of next year, the company will maintain the plant at full capacity to mid-2023.