Sierra Madre Commences Mining at Coloso, Expanding Mining Operations - Seite 2

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,

A net payable recovery of 70% (historical plant recovery plus an allowance for smelter deductions, refining costs, and concentrate transportation)

Silver price of US$22 and a gold price of $1700 and a Gold Silver Ration of 77.27:1.

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

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.

Mineral Resources that are not mineral reserves do not have economic viability. Numbers may not add due to rounding.

Indicated Resource is 3.84 Mt grading 220 AgEq (146 g/t Ag and 0.96 g/t Au) and Inferred Resource is 4.11 Mt grading 153 AgEq (113 g/t Ag ad 0.52 g/t Au). Numbers may not add due to rounding.

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

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. The technical report titled NI 43-101 - La Guitarra Technical Report, La Guitarra Mineral Resource Estimate, Guitarra Silver-Gold Project, Temascaltepec, Estado de Mexico, Mexico, has been prepared in accordance with National Instrument 43-101 Standards of Disclosure for Mineral Projects, and has been filed and is available under the Company's SEDAR+ profile at www.sedarplus.com.