GR Silver Mining Ltd. announced wide, high-grade silver (Ag) results from diamond core drilling from the recently expanded underground tunnel in the San Marcial Area, at the Plomosas Project, Sinaloa, Mexico. These assay results are from the initial three holes of an eight-hole program and confirm extensions of high-grade Ag mineralization along strike, as well as up to 170 m down dip, below the San Marcial NI 43-101 mineral resource. The successful results extend the mineralization from the initial 250 m to approximately 420 m down dip from surface. These results also suggest that the compilation of modern and historical data, combined with advanced geological modelling, has been successful in targeting higher grade mineralization on the project. The Company has successfully completed the first ever underground drill program at San Marcial, confirming extensions of the high-grade Ag mineralization at attractive widths and grades to support future resource expansion. All eight holes in the resource expansion program have now been successfully completed with assays pending for five holes: First phase of San Marcial resource expansion drilling successfully completed, defining not only continuity of high-grade Ag mineralization but also delineating new, wide hydrothermal breccias carrying Au mineralization on the footwall of the San Marcial Ag-rich hydrothermal breccia. Ag results from the San Marcial Breccia include: 881 g/t Ag over 2.0 m from 118.0 m downhole (SMI21-01). 773 g/t Ag over 18.5 m from 179.4 m downhole (SMI21-03), including: 1,792 g/t Ag over 5.6 m from 184.5 m downhole, and
516 g/t Ag over 7.9 m from 190.0 m downhole. Initial resource expansion drilling consists of 8 holes for 2,436 m drilled from recently completed underground development in the current resource area.