Great Southern Copper extends mineralisation at Cerro Negro and strengthens the potential of Chile’s Especularita Project

Great Southern Copper said new drilling at Cerro Negro in Chile extended mineralisation by 1.5 kilometres and strengthened the potential of the Especularita Project.

Great Southern Copper has announced new drill results from its Cerro Negro prospect in Chile, reporting that the latest reverse-circulation drilling has extended mineralisation up to 1.5 kilometres south of the Mostaza mine, further supporting the exploration upside of the Especularita Project. The update was released on March 23, 2026, through a regulatory announcement.

According to the company, the results come from the scout RC holes completed as part of its Phase III drilling campaign at Cerro Negro, where high-grade silver and base-metal mineralisation was intersected in all reported RC holes. Great Southern Copper said the latest results confirm additional continuity in the mineralised system and reinforce the broader exploration potential of the area.

Among the standout results, the company reported that hole RC041 returned 26 metres grading 62.8 g/t silver, 0.43% zinc and 0.19% lead from 200 metres, including 12 metres grading 101.8 g/t silver. Hole RC040 returned 16 metres grading 32.9 g/t silver and 0.19% lead from 24 metres, while RC048 intersected 6 metres grading 0.72% copper and 78.27 g/t silver from 24 metres.

Great Southern Copper also highlighted the discovery of a new near-surface copper-silver zone, which it described as a high-priority target. The company said this result could add flexibility to future exploration and development plans while expanding the scale of the mineralised system identified so far.

Another key takeaway from the announcement was the strong correlation between mineralisation and IP geophysical anomalies, which the company said supports its geological model and helps prioritise future drill targets. Great Southern Copper added that it is already moving ahead with planning for a Phase IV resource and exploration drilling programme at Cerro Negro.

The announcement comes as the company continues to focus on copper, gold and silver exploration in Chile, with Especularita remaining one of its core assets. With these latest results, Cerro Negro is emerging as a more significant target within Chile’s junior mining exploration space, particularly given current investor interest in copper- and silver-exposed projects. That final point is an inference based on the project’s commodity exposure and recent market attention to those metals.