Barksdale Resources' San Javier copper-gold project in Mexico has received positive metallurgical results.

Extraction of acid soluble copper ranged between 77% and 93% for oxide dominant samples, while the extraction of acid and cyanide soluble copper ranged from 72% and 89% for oxide dominant samples.

Testing work indicates that Barksdale will not need to use acid curing and agglomeration since these processes did not extract more copper than using only raffinate.

Barksdale will conduct further tests to optimise lift height and cycle times, and determine the effectiveness of coarser crushing.

"The results of the San Javier column leach testing programme have demonstrated strong recoveries of oxide copper while also shedding considerable light on the potential for a low-cost style operation that doesn't require agglomeration and has low acid consumption," chief executive Rick Trotman said.

The company will use these results in the calculation of the initial resource at Cerro Verde, and for an eventual preliminary economic study.

McLelland Laboratories conducted the metallurgical tests, while Barkland's consulting metallurgist Steve Dixon assisted.

Future metallurgical testing will evaluate heap leach lift heights and primary cycle times to optimise the copper in solution and acid consumption parameters, Barksdale said.

Bulk samples will also be used to evaluate increased crushed size larger than 25 millimetres on acid and cyanide dominated mineralisation.

Barksdale is also developing the Sunnyside copper-zinc-lead-silver copper project and the San Antonio copper project, both located in Arizona.