Rare earths: Key raw materials for modern technology

Rare earths are a group of 17 chemical elements that belong to the lanthanides in the periodic table, supplemented by scandium and yttrium. Despite their name, these elements are not rare, but can be found relatively frequently in the earth's crust. However, their extraction and processing is complex, which is why they are considered strategically important raw materials.

Which elements belong to the rare earths?

Rare earths include the following elements:

• Lanthanides: Lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb) and lutetium (Lu).
• Scandium (Sc)
• Yttrium (Y)

Properties of rare earths

Rare earths have unique physical and chemical properties that make them indispensable for many high-tech applications:

• Magnetic properties: Elements such as neodymium (Nd) and samarium (Sm) are used to manufacture high-performance magnets.
• Luminescence: Europium (Eu) and terbium (Tb) are used in screens and LEDs.
• Catalytic properties: Cerium (Ce) is used in catalysts and chemical processes.
• Lightweight alloys: Scandium (Sc) is used to strengthen aluminium alloys.

Challenges in the extraction of rare earths

Although rare earths are found in many regions, their extraction is complex:

• Environmental impact: Extraction is associated with considerable environmental impact, as chemical processes and large quantities of overburden are required.
• Geopolitical dependence: The majority of global production comes from a few countries, particularly China, which can lead to supply bottlenecks.
• Processing: The separation of rare earths requires complex chemical processes, as they have similar properties and are difficult to isolate from one another.

Important applications of rare earths

The unique properties of rare earths make them essential for numerous technologies:

• Magnets: Neodymium-iron-boron (NdFeB) and samarium-cobalt magnets are among the strongest permanent magnets and are used in electric motors, generators and loudspeakers.
• Electronics: Rare earths are used in smartphones, laptops, LEDs and screens.
• Energy technology: Wind turbines and electric vehicles use high-performance magnets made from rare earths.
• Medicine: Elements such as gadolinium (Gd) are used as contrast agents in magnetic resonance imaging (MRI).
• Defence: Rare earths are indispensable in radar systems, lasers and other military technologies.

Interesting facts about rare earths

Did you know that despite their name, rare earths are common in the earth's crust, but are often distributed in low concentrations? The term "rare" dates back to the time of their discovery in the 18th and 19th centuries, when these elements were only found in rare minerals. Their strategic importance is growing with the energy transition and the increasing electrification of vehicles and machines.