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GR Silver Mining Reports Drill Results at the Plomosas Silver Project Significant Near

Drill Results

GR Silver Mining Reports Drill Results at the

Plomosas Silver Project Significant Near

Surface Intervals, Including: 5.1 m @ 19.2 g/t

Au and 18.0 m @ 554 g/t AgEq

VANCOUVER, BC, Sept. 16, 2020 /CNW/ - GR Silver Mining Ltd. (TSXV: GRSL) (FRANKFURT:

GPE) (OTCQB: GRSLF) ("GR Silver Mining" or the "Company") – is pleased to announce drill

results from the Company's recently announced surface core drilling program in the Plomosas Mine

Area as well as results from the ongoing validation of historic drilling at its 100%-owned Plomosas

Silver Project ("Plomosas Project") in Sinaloa, Mexico.

The initial two drill holes completed and released are in the Plomosas Mine Area, targeting

expansion of the mineralization footprint along strike, and confirmation of attractive near surface

mineralized zones. The results received confirm the presence of wide, shallow or near surface silver-

gold-lead-zinc (polymetallic) veins and hydrothermal breccias. Our ongoing review and validation of

historic data on the same sections indicates high grade silver and gold mineralization in low

sulphidation epithermal veins outside of the polymetallic silver rich hydrothermal breccia zone. The

drilling currently in progress has validated recent geological modelling, confirming near surface zones

of wide Ag-Au-Zn-Pb mineralization. Recent access to historic workings near the area being drilled

by the Company, together with historic and recently completed drill holes, is being integrated into a

3D model to support the expansion and potential delineation of near surface resources.

The drilling completed to date, together with recently announced results, has delineated a 700 m

long mineralized system (Figure 1), consisting of multiple veins. It demonstrates the presence of, not

only the polymetallic Pb-Zn-Ag rich hydrothermal breccia hosted on the N-S oriented low angle

Plomosas Fault, but also a series of high angle, low sulphidation vein and stockwork systems,

commonly on the hanging wall or cross cut by the former hydrothermal breccias.

The mineralized zones reported in this news release represent multiple mineralization styles,

including wide, polymetallic Pb-Zn-Ag rich hydrothermal breccias, high grade Au in low sulphidation

veins/stockworks and narrow high grade Ag low sulphidation veins. The definition of wide zones, or

high grade zones close to the surface, represents a new opportunity for future shallow drilling along

strike, aiding potential resource definition.

GR Silver Mining President and CEO, Marcio Fonseca, commented, "First assay results have

now been received from GR Silver Mining's own drilling program at Plomosas. We continue to

encounter evidence of a large hydrothermal system at the Plomosas Mine Area with the

identification of wide mineralized intervals or high grade zones representing mulltiple

mineralization styles and events. Our 3D integration of the recent and historic drilling data has

proved valuable in defining the Pb-Zn-Ag mineralized zones, as well as the discovery of several

attractive near surface Ag-Au-Pb-Zn zones. The recent recommissioned access to the Plomosas

underground mine, together with surface access provide a unique opportunity to guide our surface

and underground drilling program in the upcoming months, aiming at further discoveries and

delineation of a resource in the area."

Figure 1: Drone Image of the Plomosas Mine Area (looking to the NW) - Drill Hole Location Map

(CNW Group/GR Silver Mining Ltd.)

GR Silver Mining is currently advancing its surface drilling program on the two areas marked on

Figure 1. The Company recently completed the integration of a previous ground geophysical survey

(IP) in the area and has advanced its program of underground mapping and sampling.

The initial

4,500 m

surface core drilling program is expected to continue through 2020 and has a dual

focus: shallow drilling (up to

150 m

below surface) to expand the known mineralized zones along

strike at the Plomosas Mine and San Juan-La Colorada Areas, and follow-up drilling on several new

high-grade Au-Ag low sulphidation epithermal vein occurrences at

Yecora

and El Saltito (see

news release dated

July 15, 2020

).

The planned drill sites on the Plomosas Project are located in the Plomosas Mine Area and San

Juan Trend areas where historic drilling was completed by previous owners, however GR Silver

Mining have outlined un-drilled areas with additional multiple epithermal veins along strike and at

shallow depth.

In addition to drill testing the areas with historic drill holes at the Plomosas Project, the Company will

also commence initial reconnaissance and surface exploration on 11 priority targets identified as

displaying potential for new discoveries.

Table 1 summarizes the most significant drill assay results for this set of drill holes released for the

Plomosas Mine Area.

Table 1: Summary Surface Drill Hole Results - News Release

September 16, 2020

(Plomosas

Mine Area)

SURFACE DRILLING PROGRAM 2020

Hole No.

From

(m)

To

(m)

Drilled

width

(m)

Est.

true

width

(m)

Ag

g/t

Au

g/t

Pb

%

Zn

%

AgEq

g/t

PLS20-01

8.0

16.5

8.5

6.0

85

0.4

1.1

0.6

177

includes

11.5

15.0

3.5

2.5

172

0.9

2.7

1.4

387

PLS20-02

72.4

98.1

25.7

22.3

48

0.1

0.3

0.6

85

101.0

149.0

48.0

41.6

na

na

0.1

0.5

includes

139.0

146.9

7.9

6.8

na

na

0.4

1.4

HISTORIC DRILLING DATA

Hole No.

From

(m)

To

(m)

Drilled

width

(m)

Est.

true

width

(m)

Ag g/t

Au g/t

Pb %

Zn %

AgEq

g/t

PLS-3

74.2

88.3

14.1

12.2

46

na

0.1

0.2

55

98.8

103.9

5.1

4.4

16

19.2

0.1

0.1

1,986

PLS-6

77.5

80.7

3.2

3.2

74

0.2

0.2

0.3

87

237

136.8

145.8

9.0

4.5

na

na

0.4

1.0

241

51.0

51.7

0.8

0.6

163

0.3

0.6

0.7

232

251

58.0

59.1

1.1

06

136

na

0.9

1.1

251

119.3

123.7

4.4

2.5

na

1.8

0.1

na

261

206.5

226.5

20.0

15.3

na

1.2

na

na

268

163.0

168.9

5.9

4.5

73

0.3

0.2

0.4

127

315

21.0

39.0

18.0

16.9

321

0.9

2.7

1.9

554

318

36.0

50.0

14.0

9.0

30

1.7

1.3

2.0

318

PSD-1

77.8

101.5

23.7

20.5

81

na

na

na

PSD-2

75.0

88.7

13.7

11.9

44

na

0.1

0.3

93.6

100.8

7.2

6.2

na

na

0.3

1.0

121.7

132.6

10.9

9.4

na

0.3

0.2

1.1

PSD-3

95.1

108.0

12.9

11.2

na

na

0.4

0.5

PSD-5

84.3

91.3

7.0

7.0

32

na

na

na

PSD-7

63.3

65.6

2.4

2.2

83

na

na

na

75.5

96.6

21.0

19.3

27

na

na

na

109.7

125.0

15.3

14.0

na

na

0.2

0.4

PSD-11

89.3

103.3

14.0

13.8

37

na

na

na

SD-83

61.3

66.7

5.5

5.2

18

na

0.1

0.2

*

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 drill holes in this news release were generated by a core drilling campaign initiated by the

Company in Q3/2020 (PLS20-01 and PLS20-02), and historical drill holes completed by Grupo

Mexico. Neither of the drill sets were previously released.

The area being drilled has a series of outcrops representing quartz stockwork veining and locally

hydrothermal breccias hosted in a Tertiary volcanic bimodal andesitic-rhyolitic sequence commonly

intruded by rhyolitic dykes. Structurally, the area is marked by a series of high angle NW trending

faults which are commonly intersecting the N-S low angle Plomosas Fault, a common host structure

for Ag-Au-Pb-Zn polymetallic hydrothermal breccias (

link to cross section 1

,

link to cross section 2

).

Alteration is mainly represented by a propylitic assemblage containing chlorite-epidote-quartz-pyrite

and abundant specular hematite. Locally on surface, argillic alteration halos and large oxidized zones

are observed, a result of previous accumulation of pyrite and other sulphides. The polymetallic

mineralization is mainly represented by fine galena and sphalerite, common hematite-quartz

cemented hydrothermal breccias and filling veins. Late stage quartz Ag-Au epithermal veining is

commonly observed overprinting Ag-Pb-Zn mineralization in the hydrothermal breccias.

Table 2 lists the drill hole intervals previously not sampled ("NS") for this group of released holes.

The Company continues to investigate 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

PLS-3

0.00 m to 74.2m

NS

PLS-6

0.00 m to 59.1 m

NS

237

0.00 m to 18.95 m

NS

241

0.00 m to 18.05 m

NS

251

0.00 m to 24.35 m

NS

261

0.00 m to 152.15 m

NS

268

0.00 m to 99.45 m

NS

PSD-11

0.00 m to 89.3 m

NS

SD-83

0.00 m to 61.3 m

NS

All numbers are rounded. NS - Core not assayed

Table 3: Drill Hole Locations – News Release

September 16, 2020

(Plomosas Mine Area)

Hole No.

East (m)

North (m)

RL (m)

Azimuth

Dip

Depth (m)

PLS20-01

451,586

2,552,252

940

270

-60

150.85

PLS20-02

451,486

2,551,539

986

0

-90

165.0

PLS-3

451,490

2,551,532

977

0

-90

105.85

PLS-6

451,490

2,551,532

977

90

-70

169.6

237

451,483

2,552,240

958

330

-65

201.2

241

451,502

2,552,207

959

308

-70

85.3

251

451,484

2,552,184

975

308

-60

160.25

261

451,404

2,552,189

1,010

308

-67

291.9

268

451,418

2,552,210

1,005

308

-70

255.05

315

451,282

2,552,218

795

45

-90

84.3

318

451,282

2,552,218

795

326

-53

71.65

PSD-1

451,474

2,551,541

980

270

-81

145.5

PSD-2

451,474

2,551,541

980

90

-86

260.15

PSD-3

451,477

2,551,538

980

90

-71

251.7

PSD-5

451,477

2,551,538

980

53

-50

214.0

PSD-7

451,477

2,551,538

979

53

-80

131.8

PSD-11

451,431

2,551,511

977

55

-70

379.85

SD-83

451,488

2,551,509

985

55

-80

316.2

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 had previously been drilled. This represents an opportunity for the Company's 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 Company 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 at

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.

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. In

August 2020

, GR Silver Mining commenced its drilling

program in the area to investigate extensions to known mineralization and to guide new discoveries,

part of a planned resource estimation in 2021.

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.

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.

View original content to download multimedia:

http://www.newswire.ca/en/releases/archive/September2020/16/c7086.html

%SEDAR: 00040149E

For further information:

+1 (604) 202 3155, Email: [email protected]

CO: GR Silver Mining Ltd.

CNW 07:30e 16-SEP-20