Low impact CSIRO gold extraction process to be assessed at Tunkillia

Minotaur Exploration has announced that it has signed a contract to conduct field trials of a new CSIRO in-situ gold extraction process at the Tunkillia gold project in South Australia. Minotaur Exploration and the Commonwealth Scientific and Industrial Research Organisation (CSIRO) have entered into a collaborative research agreement for the conduct of field trials of CSIRO’s recently developed process to recover gold from the oxide zone of the Tunkillia gold deposit.

CSIRO’s process, if it is validated through field trials, potentially obviates the need for pre-stripping and open cut mining of the oxide resource. No crushing, grinding or cyanide circuits would be required, as are usually required in gold processing. Waste dumps and tailings dams would also not be required and the likely environmental impact is therefore reduced. Operating and capital investment costs are expected to be lower and implementation timelines potentially shorter than for conventional installations.

The method involves leaching of gold in-situ in the host rock, into solution, and recovery of the gold from the solution after abstraction from boreholes drilled into the rock mass. No cyanide compounds are used, reducing hazardous material considerations and potential contamination. The trials will focus on modelling of ground water movement and transmission of the leach solution through natural fracture pathways in the host rock.