Sunstone Metals Extends Known Mineralisation at Bramaderos Gold-Copper Project

Sunstone Metals (ASX: STM) has returned long intervals of gold-copper mineralisation in two drill holes at the Porotillo, Copete, and Melonal prospects outside of the existing 3.6 million ounce mineral resource at its Bramaderos project in Ecuador.

A total of 25 holes for 4,776 metres were completed at the targets from February to June, with the final hole at Porotillo intersecting 175.7m at 0.5 grams per tonne gold equivalent (0.32g/t gold and 0.11% copper) from surface.

Higher-grade zones were encountered in the upper and lower parts of the hole and the mineralisation is reported to be open at depth and to the south.

Drilling and trenching at Porotillo intersected significant mineralisation over a northwest-southeast extent of 550m and a northeast-southwest extent of up to 240m, while grade shells at both targets revealed several domains of gold-copper mineralisation grading more than 0.5g/t AuEq.

Expanding Mineralisation

Sunstone managing director Patrick Duffy said exploration had continued to expand the known mineralisation at Bramaderos over significant areas.

“The Porotillo discovery now measures a large area of around 550m by 240m, and this will feed into our impending resource update, along with other significant areas of mineralisation outlined by our recent drilling and trenching campaigns,” he said.

“Assays are pending for four additional holes and nine channels at Melonal and a further three long trenches at Porotillo before we commence the mineral resource update—these additional assay results will be received during August and early September.”

Sunstone is also currently drilling a 1200m-long exploration hole at the Limon deposit targeting a deeper porphyry gold-copper system.

Bramaderos Growth Potential

The Bramaderos project contains an MRE of 220 million tonnes at 0.5g/t AuEq for 3.6Moz AuEq and a porphyry exploration target of between 4.1Moz and 11.2Moz AuEq within up to 505Mt at a grade between 0.41g/t and 0.68g/t.

A recent scoping study for the project established its viability and large growth potential and Sunstone is now focused on further growing the resource while advancing project studies towards development.

The Limon deposit hosts an exploration target of between 900,000 tonnes and 1.7Moz AuEq within 30Mt and 44Mt grading between 0.9g/t and 1.2g/t.

These latest results bring the total number of mineralised holes drilled into the cluster of porphyry systems outside of the Bramaderos resource to 26, further demonstrating the potential for growth beyond the existing resource envelope.