___________________________________________________________________________________

17 December 2025

Tiernan Gold Completes Qualifying Transaction

Further to previous announcements, Hochschild Mining PLC ("Hochschild" or the "Company") (LSE: HOC) (OTCQX: HCHDF) is pleased to confirm that Tiernan Gold Corp. ("Tiernan"), previously a wholly-owned indirect subsidiary, has completed its qualifying transaction (the "Qualifying Transaction").  As a result, trading in Tiernan's common shares is expected to commence on the TSX Venture Exchange on or about 19 December 2025, under the ticker symbol "TNGD". Tiernan is focused on advancing the large-scale open-pit heap leach Volcan gold project located in the Maricunga region of Chile.

For additional information on the Qualifying Transaction, please see the separate press release issued by Tiernan dated 17 December 2025.

As announced on 19 November 2025, Hochschild has received C$16.5 million following the sale of a part of its holding in Tiernan, which was completed concurrently with the recent brokered private placement. Consequently, Hochschild now has a 69.8% shareholding in Tiernan (61.9% on a fully diluted basis).

_____________________________________________________________________________________

Enquiries:

Hochschild Mining PLC

Charles Gordon                                                                                                                                                                                                                               +44 (0)7739 320982

Head of Investor Relations

Hudson Sandler

Charlie Jack                                                                                                                                                                                                                                       +44 (0)207 796 4133

Public Relations

_____________________________________________________________________________________

About Hochschild Mining PLC

Hochschild Mining PLC is a leading precious metals company listed on the London Stock Exchange (HOCM.L / HOC LN) and crosstrades on the OTCQX Best Market in the U.S. (HCHDF), with a primary focus on the exploration, mining, processing and sale of silver and gold. Hochschild has over fifty years' experience in the mining of precious metal epithermal vein deposits and operates two underground epithermal vein mines: Inmaculada, located in southern Peru; and San Jose in southern Argentina, and an open pit gold mine, Mara Rosa, located in the state of Goiás, Brazil. Hochschild also has the Monte do Carmo Advanced Project and numerous long-term projects throughout the Americas.

Important notices

This announcement is not for release, publication or distribution, in whole or in part, directly or indirectly in, into or from any jurisdiction where to do so would constitute a violation of the relevant laws or regulations of such jurisdiction.

This announcement is for information purposes only and is not intended to and does not constitute, or form part of, an offer to sell or an invitation to purchase any securities or a solicitation of an offer to buy, otherwise acquire, subscribe for, sell or otherwise dispose of any securities pursuant to the Transaction or otherwise, nor shall there be any purchase, sale, issuance, transfer or exchange of securities or such solicitation pursuant to the Transaction or otherwise in any jurisdiction in which such offer, invitation, solicitation, purchase, sale, issuance or exchange is unlawful.

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 release.

Forward-looking statements

This announcement contains certain forward-looking statements, including such statements within the meaning of Section 27A of the US Securities Act of 1933, as amended, and Section 21E of the Securities Exchange Act of 1934, as amended. In particular, such forward-looking statements may relate to matters such as the business, strategy, investments, production, major projects and their contribution to expected production and other plans of Hochschild Mining PLC and its current goals, assumptions and expectations relating to its future financial condition, performance and results.

Forward-looking statements include, without limitation, statements typically containing words such as "intends", "expects", "anticipates", "targets", "plans", "estimates" and words of similar import. By their nature, forward-looking statements involve risks and uncertainties because they relate to events and depend on circumstances that will or may occur in the future. Actual results, performance or achievements of Hochschild Mining PLC or members of its group may be materially different from any future results, performance or achievements expressed or implied by such forward-looking statements. Factors that could cause or contribute to differences between the actual results, performance or achievements of Hochschild Mining PLC or members of its group and current expectations include, but are not limited to, legislative, fiscal and regulatory developments, competitive conditions, technological developments, exchange rate fluctuations and general economic conditions. The Company cautions against undue reliance on any forward-looking statement or guidance, particularly in light of the current economic climate. Past performance is no guide to future performance and persons needing advice should consult an independent financial adviser.

The forward-looking statements reflect knowledge and information available at the date of preparation of this announcement. Except as required by the UK Listing Rules and applicable law, Hochschild Mining PLC does not undertake any obligation to update or change any forward-looking statements to reflect events occurring after the date of this announcement. Nothing in this announcement should be construed as a profit forecast.

_____________________________________________________________________________________

LEI: 549300JK10TVQ3CCJQ89

- ends -