PERTH (miningweekly.com) – Copper miner Oz Minerals has completed the ramp-up of its Carrapateena mine, in South Australia, reaching a mine production rate of 4.25-million tonnes a year during November.
“While the mill achieved nameplate capacity in March, the mine production ramp-up has continued throughout the year and has been completed some six months earlier than originally anticipated,” MD and CEO Andrew Cole said on Friday.
“This significant milestone is a credit to all concerned,” he added.
Cole told shareholders that the cave continued to perform well, caving through the upper Whyalla zone on November 27, with the cave now some 260 m from surface, further de-risking the establishment of the cave.
The underground operation is expected to have an estimated mine life of some 20 years, with the project currently estimated to host 950-million tonnes, at 0.57% copper and 0.25 g/t gold for 5.4-million tonnes of contained copper and 7.6-million ounces of gold.
Ore reserves at Carrapateena are estimated at 220-million tonnes, grading 1.1% copper and 0.45 g/t gold for 2.3-million tonnes of contained copper and 3.1-million ounces of gold.
A June prefeasibility study on a block cave expansion of the Carrapateena project, based on the conversion of the lower portion of the current sub-level cave into a series of block caves, found that the expansion would unlock Carrapateena’s potential to be a multi-generational, lowest quartile cash cost producing province.
The study estimated that a capital investment of between A$1.2-billion and A$1.3-billion would be required for the two block caves, with the capital investment weighted towards 2025 to 2027 for surface infrastructure to increase the production rate.