Gem Diamonds Limited - Resignation of Non-Executive Director

1 October 2025

Gem Diamonds Limited

Resignation of Non-Executive Director

Gem Diamonds Limited (LSE: GEMD) ("Gem Diamonds", the "Company" or the "Group") announces that Mazvi Maharasoa, Non-Executive Director, has informed the Board of Directors (the "Board") of her decision to resign from her position with effect from 31 December 2025, in order to pursue other opportunities.

Mazvi has served as a valued member of the Board, contributing to the Company's governance and strategic oversight during her tenure.

The resulting Board composition supports a strategic Board optimisation and will continue to be appropriate for the size of the Company. As Mazvi will remain in office until 31 December 2025, the restructuring of the Board Committees and allocation of the designated Non-Executive Director for workforce engagement to be effective from 1 January 2026, will be announced in due course and will remain in full compliance with the provisions of the UK Corporate Governance Code.

Harry Kenyon-Slaney, Non-Executive Chairman, commented:

"On behalf of the Board, I would like to sincerely thank Mazvi for her significant contribution to the Company during her tenure. We wish her all the very best for the future. The Board remains confident that Gem Diamonds' leadership retains the right balance of skills and experience to support the Company's strategy going forward."

FOR FURTHER INFORMATION:

Gem Diamonds Limited

Kiki Constantopoulos, Company Secretary

ir@gemdiamonds.com

Celicourt Communications

Mark Antelme / Charles Denley-Myerson

Tel: +44 (0) 207 777 6424

ABOUT GEM DIAMONDS:

Gem Diamonds is a leading global diamond producer of high value diamonds. The Company owns 70% of the Letšeng mine in Lesotho. The Letšeng mine is famous for the production of large, exceptional white diamonds, making it the highest dollar per carat kimberlite diamond mine in the world.