GR Silver Mining Ltd. provided an update to the market on its 2021 reconnaissance drilling program at the Plomosas Project, in Sinaloa State, Mexico. This drill program is focused primarily on new areas, recognized as attractive sites for NW or NE trending, high-grade Au-Ag mineralized veins. Additionally, the company provide an update on the discovery of the sulphide-rich mineralization in the footwall of the San Marcial resource area. Highlights: Loma Dorada ? initial logging has identified a set of NE trending quartz-sulphide veins, interpreted to connect with the San Juan Area, located 1.2 km to the south. San Marcial - Underground drilling has successfully extended the mineralized breccia 100 m down dip, below the mineral resource boundary, and has also identified a broad sulphide-rich zone hosted by a volcano-sedimentary unit. El Trampol?n ? a N-S trending epithermal vein system, along strike from historic underground workings. El Saltito ? a 2.5 km long NW-SE trending epithermal vein system including the northern and southern extensions of historic shallow Ag-Au underground workings. GAP Area ? a series of NW-SE trending epithermal veins, located between San Marcial and San Juan, discovered as a result of recent geological, geochemical and geophysical surveys. Plomosas South ? presence of sulphide-rich, steeply dipping veinlets hosted within NE-SW trending structures on the edge of intrusive dioritesThe following is a summary description of the drilling targets being tested. Loma Dorada is one of GR Silver's high priority targets for reconnaissance drilling. The Loma Dorada target is characterized by a prominent 1.5 km x 0.5 km iron-rich soil color anomaly (Figure 1) associated with intense oxidization and argillic alteration, as well as Au and Ag geochemical anomalies. The broad zone of hydrothermal alteration with disseminated sulphide and quartz-sulphide veining (Figure 1) is located 1.2 km NW of San Juan. Ongoing drilling is delineating new Ag-Au mineralized zones of low to intermediate sulphidation epithermal characteristics close to surface. The primary geological concept at Loma Dorada is to test the northern extension of the San Juan - La Colorada vein system. GR Silver's drilling to date has resulted in the discovery of typical epithermal veins with textures such as comb, lattice and bladed silica/quartz veins. SAN MARCIAL: The first underground drill program is underway at San Marcial aiming to identify new Au-Ag zones in the footwall area outside of the mineral resource and to extend the San Marcial hydrothermal breccia down dip. The main drill targets include: Shallow ground geophysical anomalies (magnetometry, chargeability and resistivity) related to a sulphide-rich volcano-sedimentary unit in the footwall of the existing mineral resource. The down dip extension of the San Marcial hydrothermal breccia to expand the current NI 43-101 mineral resource. Prospective narrow high-grade Au mineralization, as reported by previous drilling. Similar zones of elevated chargeability are found over several kilometres further S and SE of the resource area, untested by drilling, and remain attractive targets for future exploration. Resistivity and magnetic data are helping to understand the geology of this area, with definition of large intrusive (diorite and granodiorite) units, as well as identifying new drill targets. The current exploration program at Plomosas South is focused on three potential mineralization styles: the southerly extensions to the Plomosas Ag-Pb-Zn mineral system, hosted by the Plomosas Breccia; the occurrence of a set of NE-SW striking Au-Cu veins and NW-SW trending Ag-Au veins which are historically identified cross-cutting the Plomosas mineralization at different levels within the historic Plomosas mine; and the occurrence of high-angle Au mineralization at the contact between a diorite sill and the volcanic/volcaniclastic host rock sequences.