Good grades from rock chip sampling at its Teresita prospect at Especularita in Chile lifted shares in Great Southern 6% to 1.28p.
While chip samples are at best a promising indicator, Great Southern was sufficiently impressed to increase its acreage in the region just in case.
Plans are being laid for a scout drilling programme, which Sam Garrett, chief executive, said should help identify multiple deposit types of high-grade copper and gold mineralisation.
Shares rose 0.08p to 1.28p