Altona Rare Earths - Research Note

22 September 2025

ALTONA RARE EARTHS PLC

("Altona" or "the Company")

RESEARCH NOTE

Altona (LSE: REE), a resource exploration and development company focused on critical raw materials in Africa, announces that a new research note has been published by Optimo Capital Ltd. It can be accessed by using the following link:

https://www.optimocapital.co.uk/s/Altona_Rare_Earths_Update_Optimo-Sep_2025-f3zm.pdf

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Altona Rare Earths Plc

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

Imogen Ellis

Oberon Capital (Corporate Broker)                                                 +44 (0) 20 3179 5300

Nick Lovering

Adam Pollock

Aimee McCusker

About Altona Rare Earths Plc

Altona Rare Earths Plc (ticker: REE) is a London Main Market-listed exploration and development company focused on unlocking the value of critical raw materials across Africa. The Company is pursuing a diversified strategy, targeting assets with potential for near-term monetisation alongside long-term growth.

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.

The discovery of gallium mineralisation, with grades up to 550 g/t identified to date, adds further value to Monte Muambe. The Company is undertaking mineralogical and metallurgical studies to assess the potential for gallium production.

Altona's diversified portfolio also includes the Sesana Copper-Silver Project in Botswana, strategically located just 25 km from MMG's Khoemacau Zone 5 copper-silver mine. Situated on a recognised regional contact zone for copper deposits, Sesana represents a compelling exploration opportunity aligned with Altona's growth strategy.

With a unique combination of critical raw materials projects, Altona is well positioned to contribute to the global supply of highly sought commodities essential for clean energy, high technology, defence and industrial applications.

The Company and the Board remain actively focused on identifying and evaluating additional projects that align with our investment profile and strategic objectives, leveraging our extensive network and combined industry experience to uncover compelling opportunities that can drive long-term growth.