What are Rare Earth Elements?

Raw materials are essential for the functioning of the economy of an industrialised region like the EU. The global demand for non-energy raw materials has experienced an unprecedented growth in the 20th century. The notable increase in raw material consumption during recent years, the geographically uneven distribution of earth's mineral resources, the intense exploitation of most of the sizeable and high grade deposits in Europe and the restrictions on foreign investments and exports recently posed by China, make the supply of raw materials at reasonable prices one of the greatest challenges for the EU in the 21st century.

As a response to this, the EU launched the EU Raw Materials Initiative, and showed that among all the raw materials examined, the Rare Earth Elements (REE) were among the most important in terms of economic significance and predicted risk of supply. The EU is currently 100% dependent on imports, mainly from China.

Rare Earth Elements (REE) is the collective name for 17 chemically similar metallic elements (the lanthanides, Scandium and Yttrium) that occur in a wide range of REE bearing minerals and are mined collectively. They are usually divided into the light REE (LREE) and the heavy REE (HREE); the latter are found in relatively lower concentrations in the Earth's crust. Due to their chemical similarities, REE extraction is a technically complicated process, requiring intense processing.

La-Lu:These are the main rare earth elements
Element Scandium Symbol Sc Atomic number 21
Atomic weight 44.95 Density (gcm-3) 2.989 Melting Point (°C) 1541
Uses Defence technologies
Element Yttrium Symbol Y Atomic number 39
Atomic weight 88.90 Density (gcm-3) 4.469 Melting Point (°C) 1522
Uses Phosphors, Alloys, Ceramics, Nuclear, Pigments, Defence technologies
Element Lanthanum Symbol La Atomic number 57
Atomic weight 138.90 Density (gcm-3) 6.146 Melting Point (°C) 918
Uses Catalysts, Glass, Alloys, Ceramics, Defence technologies
Element Cerium Symbol Ce Atomic number 58
Atomic weight 140.11 Density (gcm-3) 8.16 Melting Point (°C) 798
Uses Catalysts, Glass, Alloys, Ceramics, Nuclear, Pigments
Element Praseodymium Symbol Pr Atomic number 59
Atomic weight 140.90 Density (gcm-3) 6.773 Melting Point (°C) 931
Uses Glass, Alloys, Magnets, Ceramics, Defence technologies
Element Neodymium Symbol Nd Atomic number 60
Atomic weight 144.24 Density (gcm-3) 7.008 Melting Point (°C) 1021
Uses Glass, Phosphors, Alloys, Magnets, Ceramics, Defence technologies
Element Promethium Symbol Pm Atomic number 61
Atomic weight 145 Density (gcm-3) 7.264 Melting Point (°C) 1042
Element Samarium Symbol Sm Atomic number 62
Atomic weight 150.36 Density (gcm-3) 7.520 Melting Point (°C) 1074
Uses Nuclear, Defence technologies
Element Europium Symbol Eu Atomic number 63
Atomic weight 151.96 Density (gcm-3) 5.244 Melting Point (°C) 822
Uses Phosphors, Ceramics, Nuclear, Defence technologies
Element Gadolinium Symbol Gd Atomic number 64
Atomic weight 157.25 Density (gcm-3) 7.901 Melting Point (°C) 1313
Uses Glass, Phosphors, Ceramics, Nuclear, Medical imaging
Element Terbium Symbol Tb Atomic number 65
Atomic weight 158.92 Density (gcm-3) 8.230 Melting Point (°C) 1356
Uses Phosphors, Magnets, Defence technologies
Element Dysprosium Symbol Dy Atomic number 66
Atomic weight 162.50 Density (gcm-3) 8.551 Melting Point (°C) 1412
Uses Magnets, Ceramics, Defence technologies
Element Holmium Symbol Ho Atomic number 67
Atomic weight 164.93 Density (gcm-3) 8.795 Melting Point (°C) 1474
Uses Glass
Element Erbium Symbol Er Atomic number 68
Atomic weight 167.26 Density (gcm-3) 9.066 Melting Point (°C) 1529
Uses Glass, Phosphors, Nuclear
Element Thulium Symbol Tm Atomic number 69
Atomic weight 168.93 Density (gcm-3) 9.321 Melting Point (°C) 1545
Element Ytterbium Symbol Yb Atomic number 70
Atomic weight 173.04 Density (gcm-3) 6.966 Melting Point (°C) 819
Element Lutetium Symbol Lu Atomic number 71
Atomic weight 174.97 Density (gcm-3) 9.841 Melting Point (°C) 1663
Uses Ceramics, Defence technologies
Periodic table highlighting the LREE and HREE.

The REE are essential raw materials for a wide range of applications, including metallurgy (metal refining and metal alloying), catalysts in the automotive and the petro-chemical industry, colouring of glass/ceramics, phosphors (LEDs, compact fluorescent lamps, flat panel displays), lasers, rechargeable solid state batteries (Ni-MH), fibre optics and others. Additionally, REE are vital elements in emerging technologies such as solid state fuel cells, superconductors, magnetic cooling, hydrogen storage and high performance permanent magnets. The latter are crucial in a variety of high-tech applications ranging from wind-turbines and hybrid cars to HD drives and cell phone speakers and microphones.

Uses of the Rare Earth Elements

Rare earths are not currently produced within the EU. However, several REE deposits have been located and some are even being developed by mining companies. To date, the Geological Surveys of European countries in which REE deposits occur, such as Sweden, Norway, Denmark, Finland and Greece, have worked to define and characterise their domestic REE resources.

Y Sr Lu Yb Tm Er Ho Dy Tb Gd Eu Sm Pm Nd Pr Ce La La - Lu