The following amendments have been made to the "Result of Share Buyback" announcement, released on 23/09/25 at 7.00am under the RNS No: 3364A:

Total Ordinary Shares to be acquired is 7,531,308 meaning the total consideration was £14,610,737.52 and On Cancellation, the Company's issued ordinary share capital will be 176,672,173 Ordinary Shares.

NOT FOR RELEASE, PUBLICATION OR DISTRIBUTION IN WHOLE OR IN PART IN, INTO OR FROM THE UNITED STATES OR ANY JURISDICTION WHERE TO DO SO WOULD CONSTITUTE A VIOLATION OF THE RELEVANT LAWS OR REGULATIONS OF THAT JURISDICTION.

THIS ANNOUNCEMENT CONTAINS INSIDE INFORMATION FOR THE PURPOSES OF ARTICLE 7 OF EU REGULATION 596/2014 AS IT FORMS PART OF UK DOMESTIC LAW BY VIRTUE OF THE EUROPEAN UNION (WITHDRAWAL) ACT 2018

8^th Floor, 54 Jermyn Street, London, SW1Y 6LX. United Kingdom

Telephone: + 44 (0)20 7629 7772  Facsimile:  + 44 (0)20 7629 7773

E mail: griffin@griffinmining.com

23^rd September 2025

Result of Share Buyback via Reverse Accelerated Bookbuild

Related Party Transaction

Total Voting Rights

Following the launch announcement on 19 September 2025 (the "Launch Announcement"), Griffin is pleased to announce the final results of the share buyback to purchase ordinary shares of $0.01 each in the Company ("Ordinary Shares") via a reverse accelerated bookbuild (the "RABB Buyback").

Pursuant to the RABB Buyback, 7,531,308 Ordinary Shares will be acquired at a price of 194 pence per Ordinary Share (the "Buyback Price") for total consideration of £14,610,737.52 by Panmure Liberum, acting as principal. The Ordinary Shares purchased by the Company pursuant to the RABB Buyback will be cancelled (the "Cancellation").

On Cancellation, the Company's issued ordinary share capital will be 176,672,173 Ordinary Shares and the total number of voting rights in the Company will be 176,672,173. This figure may be used by Shareholders as the denominator for the calculations by which they will determine if they are required to notify their interest in, or a change to their interest in, the Company, under the Disclosure Guidance and Transparency Rules of the Financial Conduct Authority.

As a result of the RABB Buyback, there have been the following changes to the holdings of the following Directors and their connected persons:

The Company purchasing 5,232,624 Ordinary Shares from Richard Griffiths constitutes a related party transaction under Rule 13 of the AIM Rules, due to their status as a Substantial Shareholder (as defined under the AIM Rules). In this context, the Directors of the Company, excluding those participating in the RABB Buyback, confirm, having consulted with the Company's nominated adviser, Panmure Liberum, that they consider that Griffin purchasing Ordinary Shares sold by Richard Griffiths in the RABB Buyback to be fair and reasonable insofar as its shareholders are concerned.

The Company purchasing 473,005 Ordinary Shares from Overbrook Management constitutes a related party transaction under Rule 13 of the AIM Rules, due to their status as a Substantial Shareholder (as defined under the AIM Rules). In this context, the Directors of the Company, excluding those participating in the RABB Buyback, confirm, having consulted with the Company's nominated adviser, Panmure Liberum, that they consider that Griffin purchasing Ordinary Shares sold by Overbrook Management in the RABB Buyback to be fair and reasonable insofar as its shareholders are concerned.

The person responsible for arranging the release of this announcement on behalf of the Company is

Roger Goodwin, Finance Director.

Enquiries:

Important Notices

The information contained within this Announcement is deemed by the Company to constitute inside information as stipulated under the Market Abuse Regulations (Regulation 596/2014) as it forms part of UK domestic law by virtue of the European Union (Withdrawal) Act 2018. Upon the publication of this Announcement via a Regulatory Information Service, this inside information is now considered to be in the public domain.

Panmure Liberum Limited ("Panmure Liberum"), which is authorised and regulated in the United Kingdom by the FCA, is acting as nominated adviser and broker exclusively for Griffin and no one else in connection with the matters set out in this announcement and will not regard any other person as its client in relation to the matters set out in this announcement and will not be responsible to anyone other than Griffin for providing the protections afforded to clients of Panmure Liberum, nor for providing advice in relation to the contents of this announcement or any other matter referred to herein. Neither Panmure Liberum nor any of its subsidiaries, branches or affiliates owes or accepts any duty, liability or responsibility whatsoever (whether direct or indirect, whether in contract, in tort, under statute or otherwise) to any person who is not a client of Panmure Liberum in connection with this announcement, any statement contained herein or otherwise or any transaction, arrangement or other matter referred to herein.

Neither Panmure Liberum nor any of its affiliates nor any of their respective directors, officers, employees, advisers or agents accepts any responsibility or liability whatsoever for, or makes any representation or warranty, express or implied, as to, the truth, accuracy or completeness of the information in this announcement (or whether any information has been omitted from the announcement) or any other information relating to Griffin, whether written, oral or in a visual or electronic form, and howsoever transmitted or made available or for any loss howsoever arising from any use of this announcement or its contents or otherwise arising in connection therewith.

All times referred to are London, UK, time unless otherwise stated.