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Sierra Madre Increases M&I Silver-Equivalent Resources at La Guitarra by 373% to 27.2 million Ounces, Inferred Silver- Equivalent Resource Increased 204%to 20.2 million Ounces

Resource Estimates

Sierra Madre Increases M&I Silver-Equivalent Resources at La

Guitarra by 373% to 27.2 million Ounces, Inferred Silver-

Equivalent Resource Increased 204%to 20.2 million Ounces

VANCOUVER, BC / ACCESSWIRE / November 1, 2023 / Sierra Madre Gold and

Silver Ltd. (TSXV:SM)(OTCQX:SMDRF) ("Sierra Madre" or the "Company") is

pleased to announce its first project-wide Resource Estimate for the La Guitarra

silver-gold mine and the Temascaltepec mining district in Estado de Mexico, Mexico.

TechSer Mining Consultants Ltd. ("TechSer") of Vancouver B.C. prepared the

Mineral Resource Estimate, David Thomas, P.Geo. and QP Geology and Cristian

Garcia, P.Eng. and QP Mining. The following tabulates the La Guitarra estimated

Mineral Resources.

Table 1: Summary La Guitarra 2023 Mineral Resource Estimate, David G.

Thomas P. Geo (Effective Date: October 24, 2023)

Class Tonnes AgEq

(g/t)

Ag

(g/t)

Au

(g/t) AgEq Ozs Ag Ozs Au Ozs

Indicated 3,842,000 220 146 0.96 27,207,000 18,073,000 118,000

Inferred 4,105,000 153 113 0.52 20,199,000 14,937,000 68,000

1. See notes following Table 3

Gregory K. Liller states, "I am extremely pleased with the results of the new mineral

resource estimation. This study validates our belief that La Guitarra has a significantly

overlooked resource base. Since April, our staff has been working on validating the

project-wide database, incorporating historical data, auditing the previously mined

areas, and refining the geologic interpretation of the vein and models. The next step to

re-opening the Guitarra mine will be a Mine and Restart Plan due in the first quarter of

2024; consisting of a capital and operating cost study, the results of which will be used

to evaluate the economic potential of the mine."

The following tabulates the Mineral Resource Estimates by Classification and Area;

Table2: Indicated Mineral Resource Estimate

Area Tonnes AgEq

(g/t)

Ag

(g/t)

Au

(g/t) AgEq Ozs Ag Ozs Au Ozs

Nazareno 310,000 257 215 0.55 2,564,000 2,141,000 5,000

Coloso 432,000 346 221 1.61 4,806,000 3,071,000 22,000

Guitarra 1,649,000 220 123 1.25 11,664,000 6,544,000 66,000

Sub-Total 2,391,000 248 153 1.22 19,034,000 11,756,000 93,000

Los Angeles 690,000 177 109 0.87 3,919,000 2,419,000 19,000

Mina De

Agua 761,000 174 159 0.19 4,255,000 3,899,000 5,000

Total

Indicated 3,842,000 220 146 0.96 27,208,000 18,074,000 117,000

Table 3: Inferred Mineral Resource Estimate

Area Tonnes AgEq

(g/t)

Ag

(g/t)

Au

(g/t) AgEq Ozs Ag Ozs Au Ozs

Nazareno 754,000 252 229 0.29 6,096,000 5,554,000 7,000

Coloso 374,000 317 213 1.34 3,810,000 2,565,000 16,000

Guitarra 293,000 180 113 0.87 1,690,000 1,059,000 8,000

Sub-Total 1,421,000 254 201 0.68 11,596,000 9,178,000 31,000

Los Angeles 66,000 157 76 1.05 333,000 161,000 2,000

Mina De

Agua 545,000 188 178 0.13 3,301,000 3,120,000 2,000

Subtotal UG

Mine 2,032,000 233 191 0.55 15,230,000 12,459,000 35,000

Inferred

Tailings 2,073,000 75 37 0.48 4,968,000 2,475,000 32,000

Total

Inferred 4,105,000 153 113 0.52 20,198,000 14,934,000 67,000

(1) Notes for Mineral Resource Estimate:

1. Canadian Institute of Mining Metallurgy and Petroleum ("CIM") definition

standards were followed for the resource estimate.

2. The 2023 resource models used nominal cutoff grades which are based on

mining and milling costs of US$50 for cut and fill mining, US$38 per tonne for

long-hole,

3. A net payable recovery of 70% (historical plant recovery plus an allowance for

smelter deductions, refining costs, and concentrate transportation)

4. Silver price of US$22 and a gold price of $1700 and a Gold Silver Ration of

77.27:1.

5. Assays were capped at 825 g/t for silver and 6.55 g/t for gold

6. Variable cut-off by deposit

1. Nazareno and Coloso - Block Model 135 AgEq cut-off grade (COG) and

a 1 m Minimum True Thickness

2. Guitarra - Polygonals Estimates 135 g/t AgEq COG and a 1 m Minimum

Horizontal Width

3. Los Angeles - Block Model Long Hole Mining 90 g/t AgEq COG

4. Mina De Agua - East District Polygonal Estimate 135 g/t AgEq COG or

90 g/t AgEq COG and > 2 m Horizontal Width

5. The tailings used a 30 g/t AgEq COG.

7. Mineral Resources that are not mineral reserves do not have economic viability.

Numbers may not add due to rounding.

8. Numbers may not add due to rounding.

9. The estimate of mineral resources may be materially affected by: metal prices

and exchange rate assumptions; changes in local interpretations of

mineralization geometry and continuity; changes to grade capping, density and

domain assignments; changes to geotechnical, mining and metallurgical

recovery assumptions; ability to maintain environmental and other regulatory

permits and ability to maintain the social license to operate

10. The 2023 resource estimate is prepared by David Thomas P.Geo. and Q.P. and

Cristian Garcia P.Eng. and QP, of TechSer in accordance with National

Instrument 43-101 Standards of Disclosure for Mineral Projects. David Thomas

and Cristian Garcia are independent qualified person ("QP's") as defined by

National Instrument 43-101. A full technical report, which is being prepared in

accordance with National Instrument 43-101 Standards of Disclosure for

Mineral Projects, will be filed and available under the Company's SEDAR

profile at www.sedar.com within 45 days of this news release.

Coloso and Nazareno Development Details

The Coloso mine supplied most of La Guitarra's production from 2015 to 2018 before

being placed on care and maintenance. The Coloso and Narareno block models

utilized wireframe models developed by First Majestic Silver which have been

validated. The Coloso veins average width is 1.5 meters and the Nazareno veins have

an average width of 4.3 meters. The Coloso mine has over 12 kilometres ("km") of

existing and accessible ramps, haulage ways, cross cuts, ventilation shafts, and

development drives. The Nazareno mineralization is accessed from the Coloso

workings by a one km meter haulage way and was under development when the mine

was closed.

Figure 1: Nazareno and Coloso Development Section

Guitarra Mine Details

The Guitarra Indicated Resources are contained in seven veins with a weighted

average width (width x tonnes) for the Indicated Resources of 3.4 meters. The

Guitarra mine has approximately 40 km of haulage ways, ramps, crosscuts, raises, and

development drives. It is accessed from the surface at five primary levels along with

several other hillside adits. A decline ramp accesses the San Rafael 1 and 2 areas and

has two ventilation shafts.

Figure 2: Guitarra Mine Section

Sierra Madre management recognized that portions of the Guitarra veins and Santa

Ana in the East District might be amenable to long-hole mining based on their

previous mining experience at the Property and historic mining methods. The Los

Angeles area in the Guitarra mine was found to have vein and stockwork

mineralization in a configuration that could be amenable to long-hole mining

methods. The Los Angeles mineralization is accessible on three haulage way levels,

several ramps, and multiple development drives. Existing ore passes on the La Cruz,

Los Angeles, San Francisco, and Garambullo levels connect to the San Rafael haulage

way, the primary haulage way to the Guitarra flotation plant.

Figure 3: Los Angeles Section

Tlacotal Project

The Santa Ana vein (also known as Mina de Agua shown in Table 2 and Table 3) in

the East District has an average width of 7.1 meters. First Majestic completed an

approved Environmental Impact Statement (MIA) to develop Santa Ana. The

operating area is called La Tlacotal, and the Company has a long-term land use

agreement on the surface.

Figure 4: Tlacotal Project Details

Sierra Madre will participate in a webinar at 2pm ET on Thursday November 2nd to

discuss the updated resource. Participants can register

here: https://us02web.zoom.us/webinar/register/WN_P5yt6om8SH-DbU22oAgppA.

The session will also be live streamed and a replay will be posted on the Adelaide

Capital YouTube Channel

here: https://www.youtube.com/channel/UC7Jpt_DWjF1qSCzfKlpLMWw.

Qualified Person

Mr. Gregory Smith, P. Geo, Director of Sierra Madre, is a Qualified Person as defined

by NI 43-101, and has reviewed and approved the technical data and information

contained in this news release. Mr. Smith has verified the technical and scientific data

disclosed herein.

About Sierra Madre

Sierra Madre Gold & Silver (TSX.V:SM)(OTCQX:SMDRF) is a precious metals

development and exploration company, focused on evaluating the potential of

restarting the La Guitarra Mine in the Temascaltepec mining district, Mexico, and the

exploration and development of its Tepic and La Tigra properties in Nayarit, Mexico.

The La Guitarra Mine is a permitted, past-producing underground mine which

includes a 500 t/d processing facility that operated until mid-2018.

The +2,600 ha Tepic Project hosts low-sulphidation epithermal gold and silver

mineralization with an existing historic resource. La Tigra, located 148 km north of

Tepic, has been mined historically; Sierra Madre´s maiden 2022 drill program at the

site intercepted shallow mineralization.

Sierra Madre´s management has played key roles for managing exploration and

development of more than 22Moz gold and 600Moz silver in combined reserves and

resources. Sierra Madre´s team of professionals has collectively raised over $1B for

mining companies.

On behalf of the board of directors of Sierra Madre Gold and Silver Ltd.,

"Alexander Langer"

Alexander Langer

President, Chief Executive Officer and Director

+1 (604) 765-1604

Contact:

[email protected]

Cautionary Note

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 news release.

This press release contains "forward-looking information" and "forward-looking

statements" within the meaning of applicable securities legislation. The forward-

looking statements herein are made as of the date of this press release only, and the

Company does not assume any obligation to update or revise them to reflect new

information, estimates or opinions, future events or results or otherwise, except as

required by applicable law. Often, but not always, forward-looking statements can be

identified by the use of words such as "plans", "expects", "is expected", "budgets",

"scheduled", "estimates", "forecasts", "predicts", "projects", "intends", "targets",

"aims", "anticipates" or "believes" or variations (including negative variations) of

such words and phrases or may be identified by statements to the effect that certain

actions "may", "could", "should", "would", "might" or "will" be taken, occur or be

achieved. Forward-looking information in this press release includes, but is not

limited to, statements with respect to the completion of the Transaction on the terms

set out in the definitive agreement (or at all) and the ability of the Company to obtain

requisite corporate and regulatory approvals for the Transaction, including but not

limited to the approval of the Exchange, Mexican antitrust approval and other

governmental approvals as currently anticipated.

In making the forward-looking statements included in this news release, the Company

has applied several material assumptions, including that the Company will be able to

receive all required regulatory approvals by the timelines currently anticipated (or at

all); and that the Company will be able to complete the Transaction on the terms of

the definitive agreement. Forward-looking statements and information are subject to

various known and unknown risks and uncertainties, many of which are beyond the

ability of the Company to control or predict, that may cause the Company´s actual

results, performance or achievements to be materially different from those expressed

or implied thereby, and are developed based on assumptions about such risks,

uncertainties and other factors set out herein, including, but not limited to, the risk

that the Company is not able to complete Transaction on the terms set out in the

definitive agreement (or at all) and the risk that the Company is unable to obtain

requisite corporate and regulatory approvals, including but not limited to the

approval of the TSX Venture Exchange, the Mexican antitrust approval and

governmental approval as currently anticipated.

Such forward-looking information represents management´s best judgment based on

information currently available. No forward-looking statement can be guaranteed and

actual future results may vary materially. Accordingly, readers are advised not to

place undue reliance on forward-looking statements or information.

SOURCE: Sierra Madre Gold and Silver