REE Focus on the UK

Focus on the UK

Background geological information and challenges

In the UK there are many documented occurrences of REE-bearing minerals, which include: monazite, allanite fergusonite, chevkinite, gadolinite and synchysite. However, in most cases these occurrences comprise only minor low tenor REE enrichment over restricted areas. For example, many of these minerals are found as rare accessory phases in some Tertiary granites, or are minor accessories to lead-zinc-fluorite mineralisation in the Northern Pennine Orefield (Walters and Lusty, 2011). To date there has been no mine production of REE-bearing minerals in the UK, nor are there any deposits in which REE reserves or resources have been reported. To date there has only been very limited evaluation of the REE potential in the UK. During the early 1990s BGS made a preliminary assessment of the REE contents of three late Caledonian alkaline intrusive complexes in north-west Scotland. Rock and drainage samples from Loch Borralan, Loch Ailsh and Loch Loyal were analysed for Ce, La and Y (Shaw and Gunn, 1993). During this period BGS undertook an assessment of the economic potential of mudstone-hosted nodular monazite in south-central Wales (Smith et al., 1994). More recently a BGS-hosted MSc student reappraised drill core from the ultramafic section of the Loch Borralan Complex to further assess its potential as a REE resource (Griffith, 2011). In 2013 BGS studied the formation of late-stage allanite-bearing veins associated with the Loch Loyal Syenite Complex (Hughes et al., 2013; Walters et al., 2013).

Location of the principal REE occurrences in the United Kingdom. From Shaw and Gunn (2020).

Even though REE minerals are known to occur in the UK, many of them are quite rare and are typically found in minor amounts in a few localities. It is worth noting that REE have never been commercially extracted in the UK, nor has there been any systematic exploration for REE.

A priority target for further investigation is the Cnoc nan Cuilean Intrusion in north-west Scotland. The hydrothermal, allanite-bearing veins that crosscut the intrusion contain the highest REE grades recorded in the UK (up to 2 wt. % TREO) (Walters et al., 2013). The known occurrence of significant hydrothermal, REE-mineralised veins associated with alkaline igneous rocks elsewhere in the world provides a strong basis for evaluating this area further. However, there is currently no commercial process for extracting REE from allanite; this coupled with the thin and discontinuous nature of the veins, makes them unlikely to be economic.

It is also important to note that previous work by BGS on the Caledonian alkaline intrusions of northwest Scotland has focussed on the PGM potential 6 of selected parts of these bodies. Systematic investigations over the entirety of these complex intrusions are recommended in order to fully evaluate their REE potential.

UK critical minerals strategy and market opportunities

A recent UK criticality assessment published by BGS, commissioned by BEIS, shows REE high on the list. The security of a rare-earth material supply is crucial to the UK’s electrification ambitions which are required to meet the UK government’s net zero target. The UK's Critical Minerals Strategy announced in 2022 aims to accelerate the growth of the UK's domestic capabilities; collaborate with international partners; and enhance international markets to make them more responsive, transparent and responsible. There are significant opportunities for the UK to deploy its expertise and forefront research assets for innovation in these areas and establish REE market share.

To build up the sustainable supply chain of REE in the UK, the UK would require diversifying the supply of REE, and exploring the possibility of mining and refining ores into metals and alloys. The UK has a leading role in R&D and education of metal refining and green chemistry. Therefore, it is important to use UK strength to develop new innovations for the chemical treatment and separation of REEs. Furthermore, there are many UK-based original equipment manufacturers (OEMs). Thus, it is also suggested to provide incentives for OEMs to develop magnet production and its end-of-life management.

Recycling of REE-containing magnets/products for secondary supply

The UK will need to secure significant quantities of REE to achieve the electrification transition. There are supply risks and limits for domestic primary production. Hence, in the long term, it is crucial to develop an ecosystem for secondary supply. The current in-use stocks could provide buffer capacity if circular economy systems are established. In the future, assuming that the net-zero targets materialise, the UK stock in products could create viable circular economy business opportunities. As most of the current plants are still at the pilot scale, it is necessary to assess the technology readiness levels (TRLs) of the existing REE recovering technologies in the UK. The UK has expertise and capability in material science and REE recycling. For example, the University of Birmingham has strong research expertise in recovering REE. Investing in R&D and establishing a secondary supply chain could expand the recycling capacity of REE and stimulate further innovation in magnets, especially research into next-generation magnet materials.