GR Silver Mining Ltd. (TSX-V: GRSL) (FRANKFURT: GPE) (OTCQB: GRSLF) is pleased to report drill results from the Plomosas Mine Area at its 100%-owned Plomosas Silver Project in Sinaloa, Mexico.

These drill results reveal the presence of wide zones of gold mineralization in addition to attractive near surface polymetallic (Ag-Pb-Zn) mineralization. The two styles of mineralization represent unmined areas located 50 m NW from a previously released section of drill hole results at the Plomosas Mine Area (Figure 1). The results define a mineralized strike length of up to 700 m, with field evidence and underground mapping indicating further continuity along strike and down dip. This news release features results from 14 diamond core holes drilled by previous companies but not previously released. The 3D geological model of results to date in the Plomosas Mine Area continues to support the Ag-rich polymetallic breccia being hosted within a shallow dipping fault and the silver-gold mineralized low sulphidation epithermal veins being hosted by multiple high angle faults.

The mineralized veins and hydrothermal breccias reported in this news release (Table 1), favour the potential delineation of shallow polymetallic resources, up to 150 vertical metres below surface. This zone has been earmarked for testing by the Company’s upcoming shallow diamond core drilling program to fully explore the extent of down-dip and along-strike continuity.

GR Silver Mining President and CEO, Marcio Fonseca, commented, “These results confirm continuity of the Plomosas Mine Area mineralized system, extending at least 700 m along strike to the NW. Additionally, our recent surface exploration work has provided evidence that the mineralized footprint extends beyond the existing drilled areas. The definition of silver-gold rich mineralized zones close to the surface represents potential for the delineation of shallow resources at the Plomosas Mine Area”.

GR Silver Mining is currently advancing its surface drilling program on the two areas marked on Figure 1, aiming to define new mineralized zones close to the surface. Modelling of mineralized zones in 3D is also underway, integrating all drill hole data, surface and underground mapping and underground channel sampling. The excellent geotechnical conditions of the historical Plomosas underground mine workings allows full access to important areas where the Company has been able to identify multiple low sulphidation epithermal veins. These veins will be the target of an underground drilling program, expected to commence in the coming months.

Table 1 summarizes the most significant drill assay results for this set of 14 drill holes released for the Plomosas Mine Area.

Table 1: Summary Surface Drill Hole Results – News Release August 11 2020 (Plomosas Mine Area)

The 14 drill holes in this news release were generated by a core drilling campaign completed by First Majestic Silver Corp. (“First Majestic”) in 2017 and 2018 (PLI17-27, PLI17-35 and PLI17-44; PLSS18-02 and PLSS18-04), and historical drill holes completed by Grupo Mexico. Neither of the drill sets were previously released. They are part of an extensive surface and underground diamond core drilling database, which GR Silver Mining continues to consolidate and validate. 

Table 2 lists the drill hole intervals previously not sampled (“NS”) for this group of released holes. The Company continues investigating previous unsampled intervals for evidence of mineralization in the core that warrants additional sampling and assaying.

Additionally, Table 3 provides collar coordinates for the drill holes presented in this news release.

Table 2: Plomosas Mine Area – Drill Hole Intervals Not Sampled (Intervals greater than 20m)

Table 3: Drill Hole Locations – News Release August 11, 2020 (Plomosas Mine Area Area)

The Company believes that the Plomosas Mine Area is part of a much larger low sulphidation epithermal system as indicated by field evidence along 1.0 km of strike length, where only 400 m of that strike has previously been drilled. This represents an opportunity for the current surface drilling program to continue discovering new mineralized zones close to the surface.

Qualified Person

The scientific and technical data contained in this News Release related to the Plomosas Project was reviewed and/or prepared under the supervision of Marcio Fonseca, P.Geo. He has approved the disclosure herein.

Quality Assurance Program and Quality Control Procedures

The recent drill holes completed by First Majestic from 2016 to 2018, followed QA/QC protocols reviewed and validated by GR Silver Mining, including insertion of blank and standard samples in all sample lots sent to First Majestic’s Laboratorio Central facilities in La Parilla, Durango, for sample preparation and assaying. Additional validation and check assays were performed by an independent laboratory at SGS de México, S.A. de C.V. facilities in Durango, Mexico. The analytical methods applied for these recent holes for Ag and Au assays comprised of Fire Assay with Atomic Absorption finish for samples above Au >10ppm and Ag >300ppm and Gravimetric Finish. Pb and Zn were analyzed using Inductively Coupled Plasma Optical Emission Spectrometry. GR Silver Mining has not received information related to the Grupo Mexico QA/QC and assay protocols and at this stage is considering the information historic for news release purposes.

About GR Silver Mining Ltd.

GR Silver Mining Ltd. is a Mexico-focused company engaged in cost-effective silver-gold resource expansion on its key assets which lie on the eastern edge of the Rosario Mining District, Sinaloa, Mexico.

PLOMOSAS SILVER PROJECT

GR Silver Mining owns 100% of the Plomosas Silver Project located near the historic mining village of La Rastra, within the Rosario Mining District. The Project is a past-producing asset where only one mine, the Plomosas silver-gold-lead-zinc underground mine, operated from 1986 to 2001. The Project has an 8,515-hectare property position and is strategically located within 5 km of the San Marcial Silver Project in the southeast of Sinaloa State, Mexico. The Plomosas Project comprises six areas with an average of 100 surface and underground drill holes in each area, geophysical and geochemical data covering most of the concession, 16 new exploration targets from which 11 have high priority for future exploration programs.

The 100%-owned assets include all facilities and infrastructure including: access roads, surface rights agreement, water use permit, 8,000 m of underground workings, water access, 60 km – 33 KV power line, offices, shops, 120-person camp, infirmary, warehouses and assay lab representing approximately US$30m of previous capital investments. The previous owners invested approximately US$18 million in exploration.

The silver and gold mineralization on this Project display the alteration, textures, mineralogy and deposit geometry characteristics of a low sulphidation epithermal silver-gold-base metal vein/breccia mineralized system. Previous exploration was focused on Pb-Zn-Ag-Au polymetallic shallow mineralization, hosted in NW-SE structures in the vicinity of the Plomosas mine. The E-W portion of the mineralization and extensions for the main N-S Plomosas fault remains under-explored. The Plomosas Silver Project has more than 500 recent and historical drill holes in six areas – Plomosas Mine, San Juan, La Colorada, Yecora, San Francisco and El Saltito. These drill holes represent an extensive database allowing the Company to advance towards resource estimation and potential project development in the near future.

SAN MARCIAL PROJECT

San Marcial is a near-surface, high-grade silver-lead-zinc open pit-amenable project. GR Silver Mining is currently drilling at the San Marcial Project, which contains 36 Moz AgEq (Indicated) and 11 Moz AgEq (Inferred), exploring recently defined new high-grade gold and silver targets along the project’s 6 km mineralized trend. GR Silver Mining is the first company to conduct exploration at San Marcial in over 10 years. The NI 43-101 resource estimate (San Marcial Project – Resource Estimation and Technical Report) was completed by WSP Canada Inc. on March 18, 2019 and amended on June 10, 2020.

Plomosas and San Marcial collectively represent a geological setting resembling the multimillion-ounce San Dimas Mining District which has historically produced more than 600 Moz silver and 11 Moz gold over a period of more than 100 years.

OTHER PROJECTS

GR Silver Mining’s other projects are situated in areas attractive for future discoveries and development in the same vicinity of Plomosas and San Marcial in the Rosario Mining District.

Figure 1: Drone Image of the Plomosas Mine Area (looking to the NW) – Drill Hole Location Map (CNW Group/GR Silver Mining Ltd.)