Sierra Madre Gold and Silver Ltd. and First Majestic Silver Corp. are pleased to announce that, pursuant to the share purchase agreement dated December 17, 2025 between Sierra Madre and First Majestic, Sierra Madre has completed its previously announced acquisition of First Majestic Del Toro, S.A. de C.V., a wholly-owned subsidiary of First Majestic incorporated under the laws of Mexico that holds a 100% interest in the Del Toro Silver Mine, as described in further detail in Sierra Madre’s and First Majestic’s news releases dated December 17, 2025 and Sierra Madre’s management information circular dated March 24, 2026. All amounts herein are expressed in Canadian dollars, unless otherwise stated in U.S. dollars (“US$”).

Alex Langer, Sierra Madre’s President and Chief Executive Officer, commented, “The acquisition of Del Toro marks an important step for Sierra Madre Gold and Silver as we advance towards mid-tier silver production. A past-producing asset of this scale is a complementary addition to our Mexico-focused silver portfolio. With existing production infrastructure in place, our focus now turns to near-term resource expansion drilling, with approximately 30,000 metres planned. This program is expected to support an updated Mineral Resource estimate, followed by a potential mine restart, positioning the asset for a return to cash flow generation. We see significant upside at Del Toro, both from resource growth and restart potential. We are excited to get boots on the ground at Del Toro and wish to thank First Majestic for their continued support and trust.”

Under the terms of the Share Purchase Agreement, and as further described in the Circular, Sierra Madre acquired all of the issued and outstanding shares of Subco in exchange for a cash payment of US$20,000,000 and the issuance to First Majestic of 10,870,000 common shares of Sierra Madre at a deemed price of $1.30 per Common Share, with each occurring at closing. In addition, within 18 months of closing the Acquisition, Sierra Madre must pay First Majestic US$10,000,000 in cash or, at Sierra Madre’s option, Common Shares at a price per Common Share equal to the market price (as determined in accordance with the policies of the TSX Venture Exchange) on the day prior to issuance of the Common Shares, subject to a maximum of 10,575,385 Common Shares, provided that if the aggregate deemed value (based on the market price of the Common Shares on the day prior to issuance) of the maximum number of Common Shares does not equal US$10,000,000, the remaining balance will be paid in cash.

The Share Purchase Agreement also sets out the following future milestone-related payments:

• if, within 48 months of closing the Acquisition, Sierra Madre files a National Instrument 43-101 Standards of Disclosure for Mineral Projects technical report over any or all of Del Toro that demonstrates mineral resources of at least 100 million ounces silver equivalent or Sierra Madre issues a news release announcing “mineral resources” of at least 100 Moz AgEq (whichever occurs earlier), Sierra Madre must pay First Majestic an additional US$10,000,000 in cash or, at Sierra Madre’s option, Common Shares at a price per Common Share equal to the market price (as determined in accordance with the policies of the TSXV) on the day prior to issuance of the Common Shares, subject to a maximum of 10,575,385 Common Shares, provided that if the aggregate deemed value (based on the market price of the Common Shares on the day prior to issuance) of the maximum number of Common Shares does not equal US$10,000,000, the remaining balance will be paid in cash; and
• if, within 60 months of closing the Acquisition, Sierra Madre achieves commercial production at Del Toro of at least 4,000 tonnes per day for 30 consecutive days, Sierra Madre must pay First Majestic an additional US$10,000,000 in cash or, at Sierra Madre’s option, Common Shares at a price per Common Share equal to the market price (as determined in accordance with the policies of the TSXV) on the day prior to issuance of the Common Shares, subject to a maximum of 10,575,385 Common Shares, provided that if the aggregate deemed value (based on the market price of the Common Shares on the day prior to issuance) of the maximum number of Common Shares does not equal US$10,000,000, the remaining balance will be paid in cash.

All Common Shares issued to First Majestic in connection with the Acquisition will be subject to a hold period ending on the date that is four months and one day following the date of issuance of the Common Shares. In addition, First Majestic has agreed to the following contractual resale restrictions on all such Common Shares issued:

As First Majestic is an insider of the Company, the Acquisition is a “related party transaction” within the meaning of Multilateral Instrument 61-101 Protection of Minority Security Holders in Special Transactions. Sierra Madre relied on the exemption from the requirement of a formal valuation for the Acquisition pursuant to subsection 5.5(b) of MI 61-101 as its Shares are not listed on a specified market. Sierra Madre was not exempt from the minority shareholder approval requirements in MI 61-101, and the Acquisition was approved by a simple majority of the votes cast at the Siera Madre’s special meeting of shareholders held on April 28, 2026 excluding, for the purposes of MI 61-101, votes attached to Shares held by First Majestic or any other persons described in items (a) through (d) of Section 8.1(2) MI 61-101. For further details, please refer to the management information circular dated March 24, 2026 available on Sierra Madre’s website at www.sierramadregoldandsilver.com and on Sierra Madre’s profile on SEDAR+ at www.sedarplus.ca.