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GR Silver Mining (C:GRSL) Reports High-grade Underground Sampling Results at Plomosas, Including Assays up to 6,128 gpt Ag over 0.2 meters.

By April 2, 2020No Comments

VANCOUVER, April 2, 2020 /CNW/ – GR Silver Mining Ltd. (TSXV: GRSL, FRANKFURT: GPE, OTCQB: GLYXF) (“GR Silver” or the “Company”) – is pleased to announce assay results for initial underground channel sampling from the San Juan underground workings at the recently acquired Plomosas Silver Project (“Plomosas”), in Sinaloa, Mexico. San Juan is one of six priority areas with underground development not yet exploited by previous owners (view photo here). The underground workings at San Juan have recently been rehabilitated by GR Silver to allow for this initial sampling program. The company is currently validating all recent and historical information, including the review of over 500 drill holes in the six priority areas and sampling mineralized zones, aiming to complete multiple resource estimations in 2020.

The most significant sample results for this release returned high-grade intervals of 0.4 m at 3,003 g/t Ag and 0.2 m at 6,128 g/t Ag both within a composite sample of 2.1 m at 532 g/t Ag, defining in situ high grade silver veins/breccia along with high-grade gold, zinc and lead mineralization (Table 1). Other important intervals include 0.5 m at 1,142 g/t Ag within a channel composite of 9.3 m at 346 g/t Ag, hosted by a hydrothermal breccia, typical of low sulphidation epithermal mineralized systems. These results provide support for the potential definition of wide, mineable, underground zones at San Juan.

The following Table 1 and Figure 1 summarize significant (>300 g/t Ag) composited and un-composited assay results (uncut, undiluted) from continuous channel sampling on the initial 140 m of the San Juan Vein (upper level).

Table 1- Results Channel Sampling San Juan Vein

San Juan Underground Development – Upper Level – Channel Sampling > 300 g/t Ag
Type Width
Au g/t Ag g/t Pb % Zn %
I COMPOSITE 2.1 0.30 552 0.73 1.04
Incl. 0.4 1.20 3,003 2.91 3.08
Incl. 0.2 2.45 6,128 5.83 6.02
II COMPOSITE 5.0 0.28 816 0.88 0.46
Incl. 0.4 0.18 1,804 1.47 0.25
Incl. 0.1 0.331 3051 4.470 0.340
Incl. 0.5 0.76 2343 1.420 0.522
III COMPOSITE 2.0 0.51 1,145 0.92 0.37
Incl. 1.3 0.46 1,324 0.84 0.32
IV COMPOSITE 2.8 0.42 482 0.45 0.37
Incl. 1.2 0.81 1,024 0.55 0.24
V COMPOSITE 9.3 0.13 346 0.69 1.03
Incl. 4.8


0.17 416 0.86 0.53
Incl. 0.5


0.31 1,142 0.80 0.55
Incl. 0.2


0.25 609 0.89 0.44


0.54 542 0.53 1.14
Incl. 0.2


0.38 1,541 0.61 2.20
VII COMPOSITE A 1.2 0.19 535 1.05 1.05
Incl. 0.9 0.07 713 0.53 1.52
COMPOSITE B 1.1 0.54 1,810 0.49 0.28
Incl. 0.4 1.09 4,698 0.88 0.34
VIII COMPOSITE (dil) 1.85 0.01 57.68 0.01 0.15
IX COMPOSITE (dil) 1.7 0.40 205.82 0.12 0.35
X COMPOSITE 1.3 0.54 341 0.09 0.19
XI COMPOSITE 1.7 0.99 460 0.13 0.36
XII COMPOSITE 2.0 0.85 511 0.08 0.38
XIII COMPOSITE 3.0 0.11 485 0.16 0.32
Incl. 1.0 0.228 1410 0.28 0.40
Incl. 1.3 0.21 263 0.19 0.30
*** The underground channel sample width of the mineralization might not be indicative of the true width of mineralization. Ongoing sampling and review of recent+ historical drilling results may provide support for future definition of the true width. (dil):  internal dilution


Figure 1- Location – Underground Workings – Channel Sampling San Juan Vein

GR Silver Mining President and CEO, Marcio Fonseca, commented“It is very encouraging to receive the first high grade silver and gold results from our ongoing underground channel sampling at the San Juan area. This area is one of our six priority areas for resource estimation at the Plomosas Project in 2020. We continue to rehabilitate the underground workings at San Juan to facilitate further sampling along the strike of the mineralization and in the lower levels. This will allow the Company to integrate new channel sample data with the recent and historical drilling data (to be released) and thus gain further understanding of not only the high-grade silver results but also the relationship with attractive gold results. Our initial studies indicate the existence of multiple high-grade silver and gold vein/breccia systems at the Plomosas Project”.

The results presented in this news release are part of a systematic sampling program implemented at regular intervals along the strike of the silver-gold mineralization in the underground workings at San Juan area. The Company is currently upgrading the extensive underground areas to working conditions, to allow further sampling. The true thickness and extent of the mineralization hosted by veins and breccias will be fully determined once all recent and historical drill results in each area are reviewed and released.

One of the most remarkable discoveries in the sampling program at San Juan has been the presence of two mineralized systems. The first system is oriented NW-SE along major regional structures hosting polymetallic (Zn-Pb-Ag with minor Au) mineralization. The second system is hosts NE-SW oriented veins-stockwork with high grade Ag-Au. These two systems represent upside potential for delineation of new resource areas.

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.

Quality Assurance Program and Quality Control Procedures (“QA/QC”)

GR Silver Mining has implemented QA/QC procedures which include insertion of blank and standard samples in all sample lots sent to SGS de México, S.A. de C.V laboratory facilities in Durango, Mexico, for sample preparation and assaying. For every sample with results above Ag >100 ppm (over limits), these samples are submitted directly by SGS de Mexico to SGS Canada Inc in Burnaby, BC. The analytical methods are 4-acid Digest and Inductively Coupled Plasma Optical Emission Spectrometry with Lead Fusion Fire Assay with gravimetric finish for silver above over limits. For gold assays the analytical methods are Lead Fusion and Atomic Absorption Spectrometry Lead Fusion Fire Assay and gravimetric finish for gold above over limits.

About GR Silver Mining Ltd.

GR Silver Mining Ltd. (GRSL.V) 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.


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 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 remains under-explored. Plomosas and San Marcial collectively represent a geological setting resembling the multi-million-ounce San Dimas Mining District which has historically produced more than 620Moz silver and 11Moz gold over a period of more than 100 years.


San Marcial is a near-surface, high-grade silver, lead, and zinc open pit amenable project. GR Silver Mining is currently expanding its NI 43-101 resource estimate at the San Marcial Project, which contains 36Moz AgEq (indicated) + 11Moz AgEq (Inferred), by defining new high-grade gold and silver targets along the project’s 6 km mineralized trend. GR Silver Mining is the first company to undertake exploration work at San Marcial in over 10 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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