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GR Silver Mining (C:GRSL) Reports Near Surface Silver and Gold Mineralization in Drill Results from the Plomosas Mine Area, Plomosas Silver Project

By August 11, 2020No Comments

Canada NewsWire

VANCOUVER, BC, Aug. 11, 2020

  • 716 gpt AgEq1 over 6.8 m (191 gpt Ag, 1.9 gpt Au, 7.1% Pb and 3.4% Zn)
  • 1,687 gpt AgEq over 0.4m (1,559 gpt Ag, 0.5 gpt Au, 1.4% Pb and 1.1% Zn)
  • 12.6m at 1.7 gpt Au, 17 gpt Ag and 0.7% Zn

VANCOUVER, BC, Aug. 11, 2020 /CNW/ – GR Silver Mining Ltd. (TSXV: GRSL) (FRANKFURT: GPE) (OTCQB: GRSLF) (“GR Silver Mining” or the “Company”) – is pleased to report drill results from the Plomosas Mine Area at its 100%-owned Plomosas Silver Project (“Plomosas 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.

1AgEq is based on long term gold, silver, zinc and lead prices of US$1600 per ounce gold, US$16.50 per ounce silver, US$0.85 per pound zinc and US$0.95 per pound lead. The metallurgical recoveries are assumed as 90% Ag, 95% Au, 78% Pb and 70% Zn.

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)

Hole No. From
Ag g/t Au g/t Pb % Zn % AgEq
PLSS18-02 357.8 359.8 2.0 2.0 350 0.2 0.3 0.2 383
includes 358.9 359.3 0.4 0.4 1,559 0.5 1.4 1.1 1,687
360.5 366.8 6.3 6.3 na 1.4 na na
PLSS18-04 377.6 387.9 10.3 10.2 52 0.2 0.1 0.5 95
PLI17-27 57.0 77.9 20.9 20.4 12 0.9 0.3 1.0 143
PLI17-35 74.8 94.7 19.9 19.2 na 0.5 0.2 0.6
PLI17-44 110.6 114.1 3.5 3.2 na 0.1 0.5 1.2
118.0 129.0 11.0 10.1 na na 0.1 0.5
216 205.0 207.8 2.8 1.8 28 1.1 1.9 3.1 284
219 7.5 14.3 6.8 4.4 191 1.9 7.1 3.4 716
226 140.0 148.9 8.9 8.8 na 1.1 na na
227 145.5 146.4 0.9 0.7 na 5.0 1.0 0.8
228 46.0 46.3 0.3 0.3 42 1.7 0.8 1.9 295
161.0 161.5 0.5 0.4 na 0.1 0.8 2.0
163.0 163.5 0.5 0.4 na na 0.3 7.2
172.0 172.6 0.6 0.5 na na 0.8 1.1
176.5 176.9 0.4 0.4 na na 2.1 3.0
216.0 216.4 0.4 0.4 na na na 5.0
229 194.5 194.9 0.4 0.4 na 2.2 2.5 0.1
199.5 199.9 0.4 0.4 na na 1.1 na
235 17.3 21.6 4.3 3.1 31 na 0.3 2.4 108
72.0 73.0 1.0 0.8 134 2.3 0.1 2.4 437
244 140.9 147.6 6.7 3.4 135 0.5 0.5 1.1 232
includes 140.9 143.3 2.4 1.2 184 na 0.4 0.9 224
148.4 154.4 6.1 3.0 4 0.8 na na
244 160.9 167.9 7.0 3.5 16 1.1 na na
167.9 169.2 1.3 0.7 6 1.2 0.1 6.1 367
182.2 194.7 12.6 6.3 17 1.7 na 0.7 209
252 147.3 156.3 9.0 5.2 15 0.5 na na
*AgEq is based on long term gold, silver, zinc and lead prices of US$1600 per ounce gold, US$16.50 per ounce silver, US$0.85 per pound zinc and US$0.95 per pound lead. The metallurgical recoveries are assumed as 90% Ag, 95% Au, 78% Pb and 70% Zn. “na” = no relevant assays. All numbers are rounded. Results are uncut and undiluted. UG: Underground Drill Hole, SURF: Surface Drill Hole

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)

Hole No. From-To (m) Sampling
PLSS18-02 0-354.15 NS
PLSS18-04 0-373.05 NS
PLI17-27 0-49.05 NS
PLI17-27 84.7-121.6 NS
PLI17-35 0-70.45 NS
PLI17-44 0-92.3 NS
All numbers are rounded. NS – Core not assayed by First Majestic

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

Hole No. East (m) North (m) RL (m) Az. Dip Depth (m)
PLSS18-02 451201 2552308 1134 111 -57 400
PLSS18-04 451201 2552308 1134 93 -77 418
PLI17-27 451180 2552225 798 90 -45 122
PLI17-35 451179 2552229 798 62 -40 132
PLI17-44 451175 2552228 798 360 -45 193
216 451485 2552288 979 308 -60 224
219 451586 2552252 941 308 -60 263
226 451535 2552298 993 52 -60 234
227 451539 2552263 976 308 -60 203
228 451539 2552263 976 0 -77 234
229 451483 2552300 988 0 -90 208
235 451494 2552246 957 308 -60 208
244 451443 2552242 980 308 -50 200
252 451439 2552242 983 308 -59 158
All numbers are rounded.

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 (“QA/QC”)

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.


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 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.


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.

Mr. Marcio Fonseca
P. Geo, President & CEO
GR Silver Mining Ltd.

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Neither the TSX Venture Exchange nor its Regulation Services Provider (as that term is defined in the policies of the TSX Venture Exchange) accept responsibility for the adequacy or accuracy of this press release.

Disclaimer for Forward-Looking Information

This press release contains forward-looking statements and information that are based on the beliefs of management and reflect the Company’s current expectations. When used in this press release, the words “estimate”, “project”, “belief”, “anticipate”, “intend”, “expect”, “plan”, “predict”, “may” or “should” and the negative of these words or such variations thereon or comparable terminology are intended to identify forward-looking statements and information. Such statements and information reflect the current view of the Company. Risks and uncertainties may cause actual results to differ materially from those contemplated in those forward-looking statements and information. By their nature, forward-looking statements involve known and unknown risks, uncertainties and other factors which may cause our actual results, performance or achievements, or other future events, to be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements.

SOURCE GR Silver Mining Ltd.

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