Placing and Restoration of Trading on AIM

Tertiary Minerals plc (AIM: TYM), the explorer focused on energy transition and precious metals in Zambia and Nevada, is pleased to announce that further to its announcement of 21 September 2026, it has conditionally raised £1,000,000 before expenses through a placing (the “ Placing”) of 1,666,666,667 new ordinary shares of 0.01 pence each in the Company (the “Placing Shares”) at a price of 0.06 pence per share (the “Placing Price”) as detailed below. The Placing was made with institutional investors and high net worth individuals and was arranged through the Company’s joint broker, SP Angel Corporate Finance LLP (“SP Angel”).

The Placing is conditional, inter alia, on approval of share authorities which will be sought at a general meeting (“General Meeting”) of the Company expected to be held on or around 27 October 2026, further details of which will be announced in due course.

Following this announcement, the Capital Access Window has now closed and normal trading in the Company's existing Ordinary Shares on AIM will resume at 7:30 a.m. on 30 September 2026.

Commenting today, Managing Director Richard Belcher said:

“I would like to take the opportunity to thank existing and new shareholders for their support. We have made significant progress at Target A1 at the Mushima North silver-copper project in Zambia this field season and aim to continue this momentum, in particular to initially test the depth extent of mineralisation below the higher-grade core, as well as assaying for critical minerals and additional metallurgical testwork.

“This is a very exciting time for the Company, and I look forward to providing updates, including the remaining assay results from the recent drilling and initial metallurgical testwork, in due course.”

Use of Proceeds

The net funds raised will be for the advancement of Target A1, Mushima North Project, including deeper drilling to test for the continuation of mineralisation beneath the oxide zone, laboratory assaying of critical minerals, expansion of metallurgical testwork, and environmental and community surveys to support an Environmental Impact Assessment, and general working capital.

Placing Details

The Placing comprises a placing of 1,666,666,667 new ordinary shares at the Placing Price. The Placing Price represents a discount of 14% to the closing bid-price to the 5-day average VWAP on 21 September 2026 when the shares were temporarily suspended pursuant to a Capital Access Window. The Placing Shares represent approximately 19% of the Company's issued ordinary share capital as enlarged by the Placing.

The Placing is conditional on Shareholder approval and a Shareholder Circular and a Notice of General Meeting will be issued in due course.

Under the terms of their engagement, SP Angel will be granted a total of 83,333,333 warrants (“Broker Warrants”). Each Broker Warrant will entitle the holder to subscribe for one new ordinary share at the Placing Price at any time within the period of 12 months from the date of Admission.

Admission

Application will be made for the Placing Shares, which will rank pari passu with the Company's existing ordinary shares, to be admitted to trading on AIM. A further announcement will be made in due course with Admission expected to be on or around 28 October 2026.

Total Voting Rights

Following Admission of the Placing Shares, the Company's enlarged issued share capital will be 8,821,022,394 ordinary shares.

The Company holds no ordinary shares in treasury. The total number of voting rights in the Company will therefore be 8,821,022,394 following Admission and this figure may then be used by shareholders as the denominator for the calculations by which they determine if they are required to notify their interest in, or a change to their interest in, the Company under the FCA's Disclosure Guidance and Transparency Rules.