San Lorenzo completes drilling at Arco de Oro; hits porphyry mineralization

  CALGARY / TheNewswire / June 4, 2026 /  San Lorenzo Gold Corp. (" San Lorenzo " or the " Corporation ") (TSXV: SLG) is pleased to provide the remaining assay results from Hole SAL 10-25 on the “San Juan” northwest extension of the Arco de Oro target.  Full assay results from Hole SAL 10–25 - that already included 102.3 metres of 1.33 g/t gold – now include multiple additional deeper intercepts throughout the 574.0 metre drill hole including 52.6 meters of 1.67 g/t gold, 48.0 metres of 0.91 g/t gold and ending in mineralization of 65.0 metres of 0.81 g/t gold.  Results are presented below. Hole SAL 10-25 (and Hole SAL 09-25) were 3.9 km step-outs from San Lorenzo’s previous “core-zone” drilling at Arco de Oro.  The holes were designed to test the significant IP anomaly evident on IP line D8 – part of additional IP data acquired during the summer of 2025. Importantly, both holes bottomed in porphyry style alteration, with the mineralization at the bottom of holes SAL 10-25 and SAL 09-25 establishing a footprint exceeding 400 metres in width.

Terence Walker, San Lorenzo’s VP of Exploration, commented: “It is gratifying – and exciting - that the mineralization that started at approximately 84 metres continued right to the bottom of hole 10 which was drilled to 574 metres.  The porphyry style mineralization, with grade, that was observed to the bottom of the hole reinforces my belief that we are in a significant system at Arco de Oro.  The system appears much larger than suggested by our early efforts at Arco – efforts that were focused on the shallower upper portion of the epithermal system that extends to surface.  With these holes, it appears that we have penetrated the upper gold-rich