Cobar Consolidated Resources (CCR) announced in mid-June its board had formally committed to development of its Wonawinta silver project 100 km south of Cobar, New South Wales. Site work has begun, and expenditures have been approved for processing plant and infrastructure. The project is expected to produce 2.5 million oz/y of silver over an initial project life of five years. Silver production is targeted before the end of 2011.
Wonawinta is Australia’s largest ‘pure’ silver project, with 14 million oz of probable silver reserves and 51 million oz of indicated and inferred resources. Mining by a contract miner will be from a series of four open-pits less than 50 m deep. The waste-to-ore ratio will be 6.2:1.
Silver bullion production will be from a conventional cyanide leach circuit. A gravity circuit will produce lead concentrate. Cash operating costs are estimated at A$10.20/oz of silver with no lead recovery and A$6.60/oz of silver with lead recovery. Capital cost is projected at less than A$30 million, and payback will be in less than one year at current silver prices or two years at a silver price of A$21/oz.
CCR has an extensive tenement position on the western margin of the Cobar basin and believes there are good prospects for discovery of additional silver and to upgrade the current resource, which would extend the project life.