The Mt Gunson Copper Project is located approximately 150 km north-west of Port Augusta, and 50 km south-west of the 5200 kt Carrapateena Copper project.
Copper Ore was discovered at Mount Gunson in 1875 and the first recorded production was from 1899. A smelter was subsequently erected in the Main Open Cut (MOC) area in 1904. Small-scale production continued in the area until the Cattlegrid deposit was discovered, and subsequently mined by CSR Limited from 1974 to 1986, with 7.2 Mt of 1.9% Cu ore mined from the Cattlegrid open pit. Together with 270,000 t of MOC ore, the tenements recorded production 127 000 t of copper, 62 t of silver and 2900 t of cobalt in concentrates.
From 1987 to around 2006, Adchem produced over 14,000 t of copper in cement for feed to the Burra cupric oxide plant from the Mt Gunson Project, principally from heap leaching of 1.2 Mt of 1.3% copper oxide ore from the MOC area, Gunyot, House and Core Shed deposits.
The leases forming the current project were subsequently acquired and are currently held by a family-owned earthmoving contractor based in Adelaide, whom previously operated their own copper oxide leach operation.
Stockpiles and in situ resources
The tenements contain stockpiles of unconfirmed grade that have previously been used as a source for leach stock, and the balance of which currently provide the basis for the planned expanded copper oxide leach operation. No contained JORC in situ resources can currently be stated for the project, despite the presence of widespread remnant mineralisation evident in the open pits. The management of Horseshoe Metals considers that a considerable portion of planned earn-in expenditure will be targeted at delivering satisfactory exploration outcomes to confirm oxide feedstock from existing surface stockpiles and remnant mining areas for a base 3 year production model that the company is currently considering.