GR Silver Mining Ltd. (TSXV: GRSL) has delivered a breakthrough discovery at its San Marcial project in Sinaloa, Mexico, with drill hole SMS25-09 intersecting 75 meters at 293 g/t silver equivalent, including a bonanza-grade core of 6.4 meters at 1,915 g/t AgEq. The results extend high-grade mineralization 100 meters below the current resource area, confirming continuity of what appears to be a large, well-preserved epithermal silver system.