ASX-listed European Resources has markedly expanded the mineral resource estimate (MRE) for the Korsnäs rare earths project, in Finland, to 15.4-million tonnes grading 1% total rare earth oxides (TREO), in the inferred category, at a 0.5% TREO cut-off.

In less than one-and-a-half years, the Korsnäs MRE has been more than doubled based on expansion of the geological and assay database, incorporation of new drilling and assay data, and refinement of the geological model.

For context, the maiden MRE of November 2024 stated a 7.1-million-tonne resource grading 1.09% TREO.

The project is centred on a historically mined lead deposit and is now recognised as part of a broader carbonatite-related rare earth element system.

European Resources says the Korsnäs resource is yet to be fully defined and exploration activities are ongoing. Importantly, this is within the context of the EU focusing on reducing its dependency on a single country supplier under its Critical Raw Materials Act of 2024.

MD Jason Beckton says the updated MRE reinforces Korsnäs as a growing European rare earth project of substance.

“The increase in the MRE reflects the value of combining preserved historical core, modern re-assaying and recent drilling, while maintaining a disciplined and conservative reporting approach.

“Just as importantly, the work completed to date continues to strengthen our geological understanding of the system and provides a sound base for the next stage of metallurgical and development studies,” Beckton explains.

He adds that together with upcoming metallurgical testwork results, European Resources is excited by the potential to develop this new source of rare earths supply for Europe.

Beckton advises that the company is following a conservative approach to its exploration and MRE estimates and with metallurgical studies still being ongoing and not having yet defined a sufficiently robust end-to-end process flowsheet, supported by recovery, concentrate and product assumptions, a higher classification of the resources is not yet justifiable.

Rather, the MRE has been reported within a conceptual framework considered sufficient to support reasonable prospects for eventual economic extraction. The cut-off grade of 0.5% TREO is consistent with previous estimates and is considered appropriate having regard to grade distribution, resource geometry, depth limits and the present stage of technical evaluation.

European Resources’ next phase of work will focus on beneficiation testwork, mini-pilot campaigns and downstream hydrometallurgical studies. For one, GTK Mintec is undertaking flotation testwork on Wet High Gradient Magnetic Separation products to improve the TREO grade and support development of an initial beneficiation flowsheet.

Additionally, a further horizontal vertical spectral ratio passive seismic programme is planned to assist refinement of priority drill targets at Korsnäs.