Critical metals

Kathryn Goodenough* goes to Greenland on a Society-sponsored hunt for the rare metals that underpin new technologie

Margins of the North Atlantic Craton: the world’s most prospective zone for the critical rare earth elements?

Seven years after the “rare earth element crisis” of 2009, the rare earth elements (REE) remain among the most critical of metals, with supply concentrated in China. Despite intense global exploration efforts, it has proved difficult for mining projects outside China to successfully commence production of the REE, due to a complex set of financial, environmental and technical concerns. REE prices have fallen, but demand remains strong – part icularly for the most critical REE used in high- strength magnets that are essential to modern technology and green energy applications, notably Nd, Dy and Pr. Phosphors also represent an important market, using Eu, Y and Tb

Unlocking the potential of Rare Earth Resources in Europe

During the last decade the non‐energy raw materials have become part of the EU’s new industrial strategy and growth agenda, with increased funding opportunities in the field of mineral resources. The four‐year (2009–2013) ProMine project has provided a well documented knowledge base of Europe's non‐energy raw material resource potential. The ongoing EURARE project is focused on enhancing the value chain perspectives for European Rare Earth Elements (REE) and the Minerals 4EU project aims to provide harmonized data on European mineral resources. This paper summarises ongoing work by the EURARE project (www.eurare.eu). REE mineral potential belts, including genetic types related to igneous, hydrothermal and sedimentary processes, have been identified across Europe. Potential REE deposits are hosted by carbonatites, alkaline igneous complexes and volcanic successions, granitic pegmatites, iron oxide copper gold deposits, and skarns, as well as secondary deposits such as laterites, bauxites and heavy mineral sands. This paper considers issues of the various deposit types with respect to REE‐bearing minerals, grades, volumes, Heavy (HREE) to Light REE (LREE) ratios, radioactive element concentrations, genetic aspects, all in a perspective of raising the awareness for exploration and the potential for exploitation

Critical Metal Mineralogy: Preface to the special issue of Mineralogical Magazine

The phrase ‘critical metals’ has become widely used over the last decade. Critical metals are those for which demand is increasing, largely due to their use in new technologies, but for which there are restrictions to supply. These supply restrictions are normally not due to a natural shortage of these elements, but instead can be attributed principally to a concentration of production in a small number of countries. Markets for many of the critical metals are still small when compared with those for major industrial metals such as copper or lead, and at the time of writing prices for almost all metals are low; as a result it can be difficult to diversify production. A number of reports, books and special issues have been published on the subject (Graedel et al., 2012, EC, 2014, Gunn, 2014, Chakhmouradian et al., 2015, Lusty and Gunn, 2015, Graedel et al., 2015)

Research and development for the Rare Earth Element supply chain in Europe.

This brochure is a product of the EURARE project, which was funded by the European Commission’s Seventh framework Programme to provide the basis upon which Europe could develop a secure supply of the rare earth elements (REE). The project ran from 2013–2017. This brochure provides a summary of European REE deposits, and describes the progress that the EURARE project has made in both improving the understanding of these deposits and processing the ores. The European value chain is also summarised, including uses and trade of the REE, and further reading suggestions are included. Further information about the project is available on the project website www.eurare.or

The structure and petrology of the Cnoc nan Cuilean Intrusion, Loch Loyal Syenite Complex, NW Scotland

In NW Scotland, several alkaline intrusive complexes of Silurian age intrude the Caledonian orogenic front. The most northerly is the Loch Loyal Syenite Complex, which is divided into three separate intrusions (Ben Loyal, Beinn Stumanadh and Cnoc nan Cuilean). Mapping of the Cnoc nan Cuilean intrusion shows two main zones: a Mixed Syenite Zone (MZ) and a Massive Leucosyenite Zone (LZ), with a gradational contact. The MZ forms a lopolith, with multiple syenitic lithologies, including early basic melasyenites and later felsic leucosyenites. Leucosyenite melts mixed and mingled with melasyenites, resulting in extreme heterogeneity within the MZ. Continued felsic magmatism resulted in formation of the relatively homogeneous LZ, invading western parts of the MZ and now forming the topographically highest terrane. The identification of pegmatites, microgranitic veins and unusual biotite-magnetite veins demonstrates the intrusion's complex petrogenesis. Cross-sections have been used to create a novel 3D GoCad™ model contributing to our understanding of the intrusion. The Loch Loyal Syenite Complex is known to have relatively high concentrations of rare earth elements (REEs), and thus the area has potential economic and strategic value. At Cnoc nan Cuilean, abundant REE-bearing allanite is present within melasyenites of the MZ. Extensive hydrothermal alteration of melasyenites here formed steeply dipping biotite-magnetite veins, most enriched in allanite and other REE-bearing accessories. This study has thus identified the area of greatest importance for further study of REE enrichment processes in the Cnoc nan Cuilean intrusion