PERTH (miningweekly.com) – ASX-listed junior Black Oak Minerals has started mining at its recently-acquired Manuka silver project, in New South Wales.

Black Oak, previously known as Southern Cross Goldfields, acquired the Manuka project, then known as the Wonawinta silver project, from the now defunct Cobar Consolidated Resources in September last year.

The project included a a process plant and infrastructure with a capacity of more than two-million tonnes a year, as well as a 60-million-ounce Joint Ore Reserves Committee-compliant silver resource and 840 km² of exploration ground.

The A$60-million project poured its first silver in 2012, but the orebody proved more complex than first thought, prompting Cobar to make adjustments to the processing plant, which resulted in a A$28.5-million impairment for the now defunct company.

Black Oak told shareholders on Wednesday that mining at Manuka was proceeding under a dry-hire arrangements, with the company’s own employees manning the fleet.

Mined ore would be stockpiled for processing once commissioning of the new ball mill and associated plant improvements were completed. Silver production was due to start in the coming weeks.

Meanwhile, Black Oak noted that the plant upgrade, which involved the installation of a larger ball mill to address the production issues experienced by Cobar had gone smoothly.

The plant upgrade had enabled several process and productivity improvements that had been earmarked for post-commissioning to be brought forward, including converting the plant from a carbon-in-pulp to a carbon-in-leach operation, to improve silver recovery.

Mining at Manuka would continue for a period of six months, after which Black Oak would start mining at its nearby Mt Boppy gold project, with the ore from that project to be delivered for processing through the upgraded Manuka plant.