High-Grade Near Surface Mineralization Drilled In San Juan Area At Plomosas

VANCOUVER - GR Silver Mining Ltd. reported on the current drilling program, demonstrating near surface high-grade silver mineralization in the San Juan Area at the Plomosas Silver Project in Sinaloa, Mexico. The surface drill hole SJS21-02 is part of the 2021 resource delineation drilling program being undertaken at the San Juan Area. Wide, high-grade silver mineralization was intercepted 55 m below surface and extends the known mineralized zone at shallow depth. Additional historical holes in the vicinity of SJS21-02 represent infill drilling data and are part of the Company's validation process of historical drill holes.

The presence of high-grade Ag-rich epithermal veins near surface at San Juan, highlights the potential opportunity for modeling of highly mineralized zones for future underground development. The expansion of the mineralization footprint along strike remains conceptual in nature, however the Company's recent drill results are providing strong support for an extensive mineralized corridor. The Company believes that Plomosas represents a district-scale project. The Company is carrying out a 11,900 m diamond core drilling program and plans to complete a resource estimation in two areas (Plomosas and San Juan) in the second quarter of 2021. Work to date has resulted in the  successful expansion of the known zones of mineralization within these two areas. The Plomosas Mine Area displays evidence of a 600 m long epithermal system, potentially extending up to 1.2 km, whereby multiple veins and discoveries have defined a much larger high-grade Ag and Au mineralized footprint. Through surface exploration and drilling, the San Juan Area, initially thought to consist of only one 400 m long epithermal vein, now appears as a 2 km long epithermal system, with at least six epithermal veins.

The Plomosas Mine Area and San Juan Area represent two areas at resource estimation stage.  Both areas have a geological footprint similar to the nearby San Marcial Project, where the company has estimated a NI 43-101 resource of 29 million ounces Ag (Indicated) and 10 million ounces Ag (Inferred). The San Marcial NI 43-101 resource represents the initial 500 m long structural corridor, which is part of a larger 6 km trend under exploration within the San Marcial Project.

The integration of the Plomosas Project and the San Marcial Project, together with concessions under acquisition located between them, provides the company full control of all of the major structural corridors on the eastern edge of the Rosario Mining District. During 2021, the Company continues to explore new mineralized zones close to surface within these exploration concessions, providing potential for additional resource growth.