VANCOUVER, BC, March 20,
2023 /CNW/ - GR Silver Mining Ltd. ("GR
Silver Mining" or the "Company") (TSXV: GRSL) (OTCQB:
GRSLF) (FRANKFURT: GPE) – is pleased to announce an independent,
updated Mineral Resource Estimate (the "Resource Estimate") in
accordance with National Instrument 43-101 Standards of Disclosure
for Mineral Projects ("NI 43-101") for the Company's wholly-owned
Plomosas Project in Sinaloa,
Mexico. The Resource Estimate was completed by ARSENEAU
Consulting Services Inc, ("ACS") of Vancouver, British Columbia, Canada, and
integrates resources for the San Marcial, Plomosas Mine and San
Juan-La Colorada Areas within the Plomosas Project.
Highlights of the Resource
Estimate (Table 1) including comparison to the previous mineral
resource estimates1 are:
- 108% increase in indicated mineral resources from 46 Moz to 97
Moz silver equivalent2 ("AgEq")
- 72% increase in indicated mineral resources from 32 Moz to 55
Moz Ag
- 61% increase in inferred mineral resources from 33 Moz to 53
Moz AgEq
- 20% increase in inferred mineral resources from 18 Moz to 22
Moz Ag
- 44% increase in average indicated mineral resource grade from
143 to 206 g/t AgEq
- 65% increase in average inferred mineral resource grade from
112 to 185 g/t AgEq
San Marcial Area
- 80% increase in indicated mineral resources from 36 Moz to 65
Moz AgEq
- 65% increase in inferred mineral resources from 12 Moz to 20
Moz AgEq
- Indicated mineral resources of 9.7 Mt at 209 g/t AgEq (148 g/t
Ag)
- Inferred mineral resources of 3.0 Mt at 200 g/t AgEq (145 g/t
Ag)
- 71% of the value of the San Marcial Resource Estimate is
comprised of silver
- 91% of the 65 Moz AgEq San Marcial indicated resources are
potentially amenable to open pit extraction
- True width of the modelled San Marcial mineralization averages
22 metres, while the SE Area discovery averages 53 metres in
thickness, supporting potential for low-cost bulk mineable open pit
and/or underground mining methods
____________________
|
1 San Marcial 2019 resource
(see News Releases dated February 7, 2019 and June 12, 2020);
Plomosas Mine and San Juan 2021 resource (see News Release dated
August 23, 2021)
|
2 Refer
to footnote below Tables 1 and 2 for AgEq definition
|
Plomosas Mine Area
- 2022 infill drilling resulted in an increase of 137% in the
indicated mineral resource tonnage
- 260% increase in indicated mineral resources from 9 Moz to 31
Moz AgEq
- Ag and AgEq grade increased by 30% and 52%, respectively, in
indicated mineral resources in relation to the previous resource
estimate
- Ag ounces represent 20% of total indicated mineral resources at
the Plomosas Mine Area
- Ag ounces represent 26% of total inferred mineral resources at
the Plomosas Mine Area
- True width of modelled mineralization at the Plomosas Mine Area
averages 20 metres, supporting potential for low-cost bulk mineable
open pit and/or underground mining methods
- 46% of the value of the Resource Estimate at the Plomosas Mine
Area is comprised of precious metals
Key Statistics
- GR Silver Mining has successfully expanded resources at a low
cost of exploration and acquisition (US$0.25/oz) at the Plomosas Project
- Since previous resource estimates in 2019 and 2021, the Company
has achieved an estimated exploration cost of US$0.17/oz AgEq discovered
- Indicated AgEq and Ag ounces have increased 331% and 206% since
the Company's inception
- Inferred AgEq and Ag ounces have increased 632% and 406% since
the Company's inception
- The proportion of total indicated resource (oz AgEq) has
increased since the previous resource estimate, now representing
65% of total resources at the Plomosas Project (Figure 1).
Figure 1 Resource Growth
GR Silver Mining Chairman and CEO, Eric Zaunscherb comments, "We
are very pleased to achieve this milestone as promised over the
past year. The conservative parameters applied, and the approach
taken, allow us to be confident in this positive outcome as we
focus on broad zones of mineralization that may be amenable to
bulk, low-cost open pit and/or underground mining methods. Delivery
of this Resource Estimate continues the advance and de-risk process
for the Plomosas Project. Management will now turn to planning next
steps, which will build on already robust resource growth, tapping
into the property's significant exploration potential. Only
approximately 300 metres of the SE Area discovery zone has been
drilled of 6 kilometres prospective contact strike length,100%
controlled by the Company. Recent surface mapping by our geologists
has peeled the geological onion and discerned the controls on
high-grade mineralization for future success. In addition,
we intend to begin attaching economic parameters to the Plomosas
Project that, in our opinion, will demonstrate its appeal. We are
very proud of, and grateful to, our team of employees and
consultants at site for making this possible."
A total of 75 GR Silver Mining drill holes (10,500 metres)
were added to the 52 holes used in the previous resource
estimate, totalling 122 holes (19,000 metres) for the San Marcial
Area including SE Area discovery. At the Plomosas Mine Area, a
total of 223 drill holes (16,380 metres) were drilled in specific
areas of the existing underground historical mine as part of the
infill drilling program. A total of 424 drill holes (60,020 metres)
comprises the Plomosas Mine Area database supporting the Resource
Estimate.
In addition to the San Marcial and Plomosas Mine Areas, the
Resource Estimate also includes the updated mineral resource
estimation for the San Juan-La Colorada Area (Figure 2). The
Plomosas Project Resource Estimate combines the three areas and
includes the SE Area discovery. The Resource Estimate adopts the
key parameter of having a reasonable prospect of economic
extraction, utilizing a combination of open pit and underground
assumptions. Capping was applied to the original assay values prior
to compositing in the mineral resource estimation process (Table
4).
A technical report is being prepared on the updated Mineral
Resource Estimate in accordance with NI 43-101 and will be
available on the Company's website and SEDAR within 45 days of the
date of this release. The effective date of the updated Mineral
Resource Estimate is March 15,
2023.
Figure 2 Location of the Three Areas Integrated
in the Plomosas Project Resource Estimate
The San Marcial Area, including the SE Area discovery, with
indicated mineral resources of 9.7 Mt at 209 g/t AgEq (148 g/t Ag)
and inferred mineral resources of 3.0 Mt at 200 g/t AgEq (145 g/t
Ag) represents approximately 78% of Ag contained in the total
Resource Estimate. Shallow infill drilling during 2022 in the 2019
resource area has enhanced the definition of high-grade silver
zones close to surface within the San Marcial mineral resource,
which is reflected in Table 2, defining the potential for an open
pit amenable portion of the San Marcial Area resource estimate.
Infill drilling in the previous resource area of the Plomosas
Mine during 2022 has enhanced the definition of silver grades
particularly closer to the surface, at shallow levels of the
historic underground mine, where the Company achieved better
delineation of high-grade Ag zones. At the lower levels of the
historic underground mine, the Pb-Zn mineralization continues to
provide a strong contribution to the Resource Estimate. Overall,
the average silver grades for indicated and inferred resources in
the Resource Estimate for the Plomosas Mine Area are slightly
higher than the 2021 resource estimate. This is reflected in the
detailed summary of the Plomosas Mine Area resource statement in
Table 2.
The Resource Estimate for the San Juan-La Colorada Area consists
primarily of an update in the geological model and limited drilling
to integrate newly interpreted structural controls into the
resource estimation. A slight increase in the gold grades can be
observed, particularly at La
Colorada, resulting from a more detailed modelling, when
compared with the previous resource estimate.
Table 1 Plomosas Project Mineral Resource
Statement ACS - March 15,
2023
|
|
|
|
Average
Grade
|
Contained
Metal
|
PLOMOSAS
|
Resource
|
Type
|
Tonnes
|
Ag
|
Au
|
Pb
|
Zn
|
Cu
|
AgEq*
|
Ag
|
Au
|
Pb
|
Zn
|
Cu
|
AgEq
|
PROJECT
|
Category
|
Mt
|
g/t
|
g/t
|
%
|
%
|
%
|
g/t
|
Moz
|
Koz
|
Kt
|
Kt
|
Kt
|
Moz
|
|
Indicated
|
OP
|
11
|
138
|
0.07
|
0.3
|
0.4
|
0.01
|
203
|
47
|
22.9
|
31
|
43
|
1
|
69
|
|
Inferred
|
OP
|
3
|
105
|
0.13
|
0.4
|
0.5
|
0.02
|
172
|
9
|
10.7
|
11
|
13
|
1
|
15
|
|
Indicated
|
UG
|
4
|
62
|
0.48
|
0.8
|
1.2
|
0.06
|
213
|
8
|
61.6
|
33
|
47
|
3
|
28
|
|
Inferred
|
UG
|
6
|
67
|
0.49
|
0.8
|
1.2
|
0.04
|
191
|
13
|
97.4
|
53
|
78
|
2
|
38
|
TOTALS
|
Total
|
Indicated
|
15
|
117
|
0.18
|
0.4
|
0.6
|
0.03
|
206
|
55
|
84.5
|
64
|
90
|
4
|
97
|
|
Total
|
Inferred
|
9
|
78
|
0.38
|
0.7
|
1.0
|
0.03
|
185
|
22
|
108.1
|
64
|
91
|
3
|
53
|
Table 2 Plomosas Project Mineral Resource
Statement ACS - March 15, 2023 – By
Area
|
|
|
|
Average
Grade
|
Contained
Metal
|
PLOMOSAS
|
Resource
|
Type
|
Tonnes
|
Ag
|
Au
|
Pb
|
Zn
|
Cu
|
AgEq*
|
Ag
|
Au
|
Pb
|
Zn
|
Cu
|
AgEq
|
PROJECT
|
Category
|
Mt
|
g/t
|
g/t
|
%
|
%
|
%
|
g/t
|
Moz
|
Koz
|
Kt
|
Kt
|
Kt
|
Moz
|
San Marcial
Area
|
Indicated
|
OP
|
9
|
146
|
0.04
|
0.2
|
0.3
|
-
|
205
|
42
|
10.2
|
16
|
28
|
-
|
59
|
|
Inferred
|
OP
|
2
|
127
|
0.03
|
0.1
|
0.2
|
-
|
173
|
6
|
1.4
|
1
|
3
|
-
|
9
|
|
Indicated
|
UG
|
1
|
176
|
0.06
|
0.3
|
0.6
|
-
|
258
|
4
|
1.5
|
2
|
4
|
-
|
6
|
|
Inferred
|
UG
|
1
|
164
|
0.03
|
0.2
|
0.4
|
-
|
229
|
8
|
1.6
|
3
|
5
|
-
|
11
|
|
Total
|
Indicated
|
10
|
148
|
0.04
|
0.2
|
0.3
|
-
|
209
|
46
|
11.7
|
18
|
33
|
-
|
65
|
|
Total
|
Inferred
|
3
|
145
|
0.03
|
0.1
|
0.3
|
-
|
200
|
14
|
3.0
|
4
|
8
|
-
|
20
|
Plomosas Mine
Area
|
Indicated
|
OP
|
2
|
93
|
0.24
|
1.0
|
0.9
|
0.07
|
193
|
5
|
11.9
|
16
|
14
|
1
|
10
|
|
Inferred
|
OP
|
1
|
66
|
0.28
|
1.0
|
1.0
|
0.06
|
174
|
2
|
7.8
|
9
|
9
|
1
|
5
|
|
Indicated
|
UG
|
3
|
35
|
0.57
|
0.9
|
1.3
|
0.08
|
204
|
4
|
58.0
|
30
|
42
|
3
|
21
|
|
Inferred
|
UG
|
2
|
38
|
0.57
|
0.9
|
1.1
|
0.06
|
175
|
3
|
39.4
|
20
|
23
|
1
|
12
|
|
Total
|
Indicated
|
5
|
54
|
0.46
|
1.0
|
1.2
|
0.08
|
200
|
8
|
69.9
|
46
|
56
|
4
|
31
|
|
Total
|
Inferred
|
3
|
46
|
0.48
|
0.9
|
1.0
|
0.06
|
175
|
5
|
47.2
|
28
|
32
|
2
|
17
|
San Juan-La Colorada
Area
|
Indicated
|
OP
|
0.1
|
161
|
0.29
|
0.3
|
0.6
|
0.02
|
211
|
0.4
|
0.8
|
0
|
1
|
-
|
1
|
|
Inferred
|
OP
|
0.2
|
104
|
0.24
|
0.5
|
0.8
|
0.02
|
158
|
0.7
|
1.5
|
1
|
2
|
-
|
1
|
|
Indicated
|
UG
|
0.1
|
90
|
0.61
|
1.1
|
0.8
|
0.04
|
198
|
0.3
|
2.1
|
1
|
1
|
-
|
1
|
|
Inferred
|
UG
|
2.6
|
33
|
0.69
|
1.2
|
1.9
|
0.04
|
182
|
2.8
|
56.4
|
31
|
49
|
1
|
15
|
|
Total
|
Indicated
|
0.2
|
121
|
0.46
|
0.7
|
0.7
|
0.03
|
204
|
0.8
|
2.9
|
1
|
1
|
-
|
1
|
|
Total
|
Inferred
|
2.8
|
39
|
0.65
|
1.1
|
1.8
|
0.04
|
180
|
3.5
|
57.9
|
32
|
51
|
1
|
16
|
|
Numbers are
rounded
|
* AgEq = calculated
from the metal prices and recoveries using the equation AgEq = ((Au
price*Au Recovery) + (Ag Price*Ag Recovery) + (Pb Price*Pb
Recovery) + (Cu Price*Cu Recovery) + (Zn Price*Zn Recovery)) / (Ag
Price*Ag Recovery)
|
(1) Mineral
Resources which are not Mineral Reserves, do not have demonstrated
economic viability
|
(2) The estimate of
Mineral Resources may be materially affected by environmental,
permitting, legal, title, taxation, socio-political, marketing, or
other relevant issues
|
(3) The Inferred
Mineral Resource in this estimate has a lower level of confidence
than that applied to an Indicated Mineral Resource and must not be
converted to a Mineral Reserve. It is reasonably expected that the
majority of the Inferred Mineral Resource could be upgraded to an
Indicated Mineral Resource with continued
exploration
|
(4) The Mineral
Resources were estimated using the Canadian Institute of Mining,
Metallurgy and Petroleum (CIM), CIM Standards on Mineral Resources
and Reserves, Definitions and Guidelines prepared by the CIM
Standing Committee on Reserve Definitions and adopted by the CIM
Council
|
|
Mineral Resource
Estimates
The mineral resource estimates for the San Marcial, Plomosas
Mine, San Juan-La Colorada Areas were provided by Dr. Gilles Arseneau, P.Geo. of ARSENEAU Consulting
Services Inc. (ACS) using Geovia Gems Version 6.8.4. The San
Marcial and Plomosas Mine mineral resources were estimated by
ordinary kriging, and the San
Juan-La Colorada mineral
resources were estimated by the Inverse Distance Squared method.
The Plomosas and San Juan models
were estimated in 5 metre cube blocks and the San Marcial grades
were estimated in 10 by 5 by 10 metre blocks. Grades were capped to
the 98th or 99th percentile from probability
plots prior to compositing to 1 metre. Block grades were estimated
in three successive passes for the San Marcial and Plomosas Mine
and four passes for the San Juan-La Colorada Area. The historical
Grupo Mexico drill holes were only used for passes two and three at
the Plomosas Mine and for passes three and four at the San Juan-La
Colorada Area. Blocks estimated with Grupo Mexico drill holes were
all classified as inferred mineral resources. Blocks estimated
during Pass 1 with at least two drill holes or Pass 2 at
San Juan, with at least four drill
holes, were classified as Indicated.
Mineral resources are reported using a dollar equivalent based
on the following metal prices and recoveries determined from recent
metallurgical tests. The mineral resources are reported using pit
constrained ("Whittle Pit Assessment") and Underground stope
optimizer ("MSO") with operational cost assumptions reported in
Table 3.
Table 3 Summary Parameters Adopted for Resource
Estimation and Mineral Resource Reporting - Plomosas Mine and San
Juan Areas
Plomosas
Project
|
Metal Prices
|
Gold US$/oz
|
$1,750
|
Silver
US$/oz
|
$22.00
|
Lead US$/lb
|
$1.10
|
Zinc US$/lb
|
$1.30
|
Copper
US$/lb
|
$4.20
|
Area
|
San Marcial
|
Plomosas
Mine
|
San Juan
|
Metallurgical
Recoveries***
|
Gold
|
0
|
86 %
|
79 %
|
Silver
|
94 %
|
74 %
|
71 %
|
Lead
|
59 %
|
69 %
|
58 %
|
Zinc
|
80 %
|
75 %
|
47 %
|
Preliminary Cost
Assumptions
Mineral Resource
Reporting****
|
Open Pit
("OP")
|
30 US$/t
|
30 US$/t
|
30 US$/t
|
Underground
("UG")
|
60 US$/t
|
60 US$/t
|
60 US$/t
|
|
*** Based on
preliminary metallurgical testwork completed in 2021 with samples
from both areas investigating potential production of precious
metal-rich concentrate
|
**** Preliminary cost
assumptions adopted in the Whittle assessment and MSO are based on
similar type deposits in Mexico where underground and open pit
operations are in progress for a throughput capacity of 1000
tpd
|
|
Capping was adopted in the Resource Estimate by each specific
domain as indicated in Table 4.
The reasonable prospect of economic extraction was defined by
generating a Whittle optimized pit shell based on the above metal
prices and recoveries and assuming a total open pit mining cost and
processing cost of US$30/t.
Underground resources were restricted to shapes defined by stope
optimizer software and assumed combined underground mining and
processing costs of US$60/t.
The mineral resource estimates are based upon drilling completed
by the Company between 2021 and 2022.
Table 4 Plomosas Project – Assay Capping Level by
Area
Metal
|
San Marcial
Silver Zone
|
San Marcial
Pb-Zn Zone
|
Plomosas
US$20 Zone (DDH)3
|
Plomosas
Pb-Zn Zone (DDH)
|
San Juan
|
La Colorada
|
Gold
|
NC
|
NC
|
15.0 g/t
|
2.5 g/t
|
3.0 g/t
|
5.0 g/t
|
Silver
|
1,800 g/t
|
850 g/t
|
800 g/t
|
200 g/t
|
825 g/t
|
350 g/t
|
Copper
|
NC
|
NC
|
1.0 %
|
1.0 %
|
NC
|
0.5
|
Lead
|
4.5 %
|
4.5 %
|
20.0 %
|
6.5 %
|
4.0 %
|
10.0 %
|
Zinc
|
5.0 %
|
5.0 %
|
15.0 %
|
8.3 %
|
8.0 %
|
13.0 %
|
|
3DDH = drill
holes
|
NC=no capping
applied
|
|
QA/QC Procedures
The Company has implemented QA/QC procedures which include
insertion of blank, duplicate 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 four 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
(>10 ppm).
Qualified Person
The mineral resource estimate was completed by independent
consultant Dr Gilles Arseneau, P.
Geo. of ARSENEAU Consulting Services Inc., a registered
professional, who is an independent Qualified Person (QP) as
defined by NI 43-101. Mineral resources are reported in accordance
with CIM (2014) Definition Standards for Mineral Resources and
Mineral Reserves in accordance with NI 43-101. Dr. Arseneau is a P.
Geo. and is qualified as a Mineral Resource estimator and has over
25 years of relevant industry experience.
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.
About GR Silver Mining
Ltd.
GR Silver Mining is a Canadian-based, Mexico-focused junior mineral exploration
company engaged in cost-effective silver-gold resource expansion on
its 100%-owned assets, located on the eastern edge of the Rosario
Mining District, in the southeast of Sinaloa State, Mexico. GR Silver Mining controls 100% of two
past producer precious metal underground and open pit mines, within
the expanded Plomosas Project, which includes the integrated San
Marcial Area and La Trinidad
acquisition. In conjunction with a portfolio of early to advanced
stage exploration targets, the Company holds 734 square kilometres
of concessions containing several structural corridors totaling
over 75 kilometres in strike length.
GR Silver Mining Ltd.
Eric Zaunscherb, Chairman &
CEO
Cautionary Statement Regarding
Forward-Looking Information
This press release contains "forward-looking statements"
within the meaning of applicable Canadian securities legislation
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.
Neither the TSX Venture Exchange nor its Regulation Services
Provider (as that term is defined in the policies of the TSX
Venture Exchange) accepts responsibility for the adequacy or
accuracy of this press release.
SOURCE GR Silver Mining Ltd.