MONTE MUAMBE: Gallium and Fluorspar Update

Altona Rare Earths PLC (LSE: REE), the resource exploration and development company advancing critical raw materials projects in Africa, is very pleased to announce that it has received from SGS Johannesburg partial mineralogy and geochemistry results of Monte Muambe gallium samples.

Laboratory results on two fenite samples collected in June 2025 confirm previous gallium results obtained using the Company's pXRF analyser, with grades of 210 and 269 g/t respectively.

In addition, mineralogy results identified the presence of fluorspar in both gallium-containing samples, with 34.00 and 26.38% Fluorite (equivalent to CaF2) respectively. The presence of fluorite had not been detected in the initial pXRF analyser assays because this device cannot analyse the chemical element fluorine.

It is also very encouraging that the fluorite content of these samples is significantly above the cutoff grade intended for the resource estimate to be prepared later this year (cut-off grades ranging from 15% to 20% CaF2 will be tested). The Company will therefore consider these rocks as potential ore for the fluorspar project. In addition, the samples contain over 45% of K-feldspar, a mineral that previous metallurgical testing has shown can easily be separated from fluorite, auguring of enhanced recoveries for this type of ore.

Mineralogical characterisation continues with the aim of confirming which mineral species contains gallium. Due to the chemical properties of this element, gallium is unlikely to be hosted in fluorite. During the flotation process, gallium concentration is therefore expected to increase in the tailings (the left-over materials) after fluorite is extracted. This may potentially enhance the economic and technical feasibility of recovering gallium from the flotation tailings.

These results also provide additional validation of the use of gallium for fluorspar exploration, which resulted in the discovery of new fluorspar outcrops announced on 28 May 2025 (assay results announced on 7 July 2025), and further strengthens the Company's confidence in increasing the fluorspar resource base through additional surface exploration and drilling planned this quarter.

Gallium is a rare metal usually extracted as a by-product from zinc and bauxite ore and is used in

a wide range of electronic and high-technology applications such as radars, light diodes and

semiconductors. Because of the superior performance of electronic components made with gallium, they are typically used in critically important military applications. Gallium is considered a strategic raw material by several jurisdictions including the European Union, with China having a quasi-monopoly on its production. China banned exports of gallium to the United States in December 2024, and this ban is still in place.

Cedric Simonet, CEO of Altona, commented:

"I am very excited to see that every fluorspar and gallium result coming back from the field and from the lab is serving to only strengthen further this project and its potential economics. I look forward to starting the resource drilling campaign during the course of this quarter and updating shareholders as this work progresses."

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Altona Rare Earths Plc

Cédric Simonet, CEO +44 (0) 7778 866 108

Louise Adrian, CFO +44 (0) 7721 492 922

Strand Hanson (Financial Adviser) +44 (0) 20 7409 3494

Christopher Raggett

About Altona Rare Earths Plc

The multi-commodity Monte Muambe Project in northwest Mozambique is a highly prospective tenement hosting rare earths, fluorspar, and gallium mineralisation. Since acquiring the project in June 2021, Altona has drilled over 7,800 metres, delivering a maiden JORC Mineral Resource Estimate of 13.6Mt at 2.42% TREO, secured a 25-year mining licence (granted December 2024), and published a Competent Person Report and scoping study for the rare earths component of the project (October 2023). The Company is actively seeking a strategic downstream rare earths partner to advance the project through the prefeasibility stage.

In parallel, Altona is progressing plans to fast-track the development of high-grade fluorspar veins identified along the western and southern margins of Monte Muambe, with a targeted production of 50,000 tonnes per annum of acid-grade fluorspar over a minimum 12-year mine life. Acid-grade fluorspar is a key input in a wide range of applications, including hydrofluoric acid and lithium battery electrolyte production, placing Altona in a strong position to supply this critical material.