The latest hole intersected 64m of gold at a grade 1.67 g/t from a depth of 144m.
Metminco believes Tesorito is a significant near surface porphyry gold target and as it is located just 800m from its Miraflores deposit would be able to share infrastructure.
In addition, negotiations have been underway for some time with AngloGold Ashanti about the development of Chuscal, a third deposit nearby.
All three lie within a 1.3km radius, said Metminco, so they can have a significant impact on the feasibility study numbers for Miraflores published last year.
Kevin Wilson, executive chairman, said the higher grades seen in the latest hole were a material step forward for Tesorito and the company.
“It demonstrates that there is potential for the company's 880,000oz resource at Miraflores to be complemented by this near surface mineralised target at the Tesorito porphyry, only 800m to the southeast.
“Importantly, any near surface, higher grade gold mineralisation delineated at Tesorito has the potential to materially improve the economics of the Miraflores feasibility study though an integrated development plan, sharing mine and process infrastructure.
“In addition, we have additional targets at Chuscal and Dosquebrados requiring follow-up, all within a potential radius of operation for a centralised plant."
Shares jumped 34% to 0.45p.
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