What are rare earth metals?

Rare earth metals are 17 elements: the 15 lanthanides plus scandium and yttrium. They are not actually rare, but difficult to separate. For magnets, neodymium, praseodymium, dysprosium, terbium and samarium are the most important.
By Team Magnetenspecialist
2 min read

Short answer: rare earth metals are a group of 17 elements: the 15 lanthanides (lanthanum to lutetium) plus scandium and yttrium. They are not actually rare (neodymium is more common than lead), but they are scattered and mixed in ore and chemically difficult to separate from each other. For magnets, neodymium, praseodymium, dysprosium, terbium and samarium are the most important.

Which rare earth metals are in magnets?

Element Symbol Role in magnets
Neodymium Nd main component of NdFeB magnets
Praseodymium Pr partly replaces neodymium ("PrNd")
Dysprosium Dy increases coercivity and temperature resistance (H, SH, UH)
Terbium Tb like dysprosium, even more effective but more expensive
Samarium Sm basis of samarium cobalt magnets (SmCo)
Gadolinium Gd MRI contrast agent; not in standard magnets

Light and heavy rare earth metals

  • Light (including lanthanum, cerium, praseodymium, neodymium): relatively abundant.
  • Heavy (including dysprosium, terbium, yttrium): much scarcer and more expensive. They mainly come from ion-adsorption clay in southern China and Myanmar.

That is why magnets for high temperatures (with dysprosium or terbium) are more expensive than ordinary N grades. Modern factories only apply dysprosium along the grain boundaries (grain boundary diffusion), so much less is needed.

Why are they strategically important?

  • Concentration: China supplies approx. 70% of mining and around 90% of separation and magnet production.
  • Export restrictions: since 2025 China requires export licences for, among others, dysprosium, terbium and samarium and for magnets containing them.
  • Growing demand: electric cars, wind turbines and robots use many neodymium magnets.
  • Europe: the Critical Raw Materials Act (2024) aims for at least 10% of critical raw materials to be mined in the EU by 2030, 40% processed and 25% recycled, and for no more than 65% to come from a single country.

Mining and the environment

The ore usually contains only a few percent of rare earth metals. Separation takes hundreds of steps of liquid-liquid extraction. This produces acidic waste streams, and with monazite radioactive residue due to thorium. Stricter environmental rules and recycling should reduce the impact. Recycling magnets from hard drives, motors and wind turbines is technically possible, but still happens on a small scale.

Frequently asked questions

Are rare earth metals really rare?

No. Cerium is about as common as copper, and neodymium more common than lead. Rich, mineable deposits are rare, though.

Are there magnets without rare earth metals?

Yes: ferrite, AlNiCo and rubber magnets. They are much weaker, however. See neodymium, ferrite or samarium cobalt?

Read also

Need help choosing? Use the Magnet Advisor or contact us.