Rare Earth Metals

A labourer works at the site of a rare earth metals mine at Nancheng county
••• Jie Zhao/Contributor/Getty Images

Rare earth metals are actually not as rare as their name might imply. Critical to high-performance optics and lasers and key to the most powerful magnets and superconductors in the world, rare earths are simply more difficult to mine than most metals and generally don't accumulate into rich ores.

This rarity, combined with the demand for the metals in high-tech applications, brings about economic and political complications that make some of the most interesting metals even more exciting.

Rare Earths in the Marketplace

According to the United States Geological Survey, as of 2000, China produced well over 90% of world demand for rare earth metals. Their ores are rich in yttrium, lanthanum, and neodymium.

In August of 2010, lingering fears over Chinese dominance of crucial rare earth supplies were brought to focus when China restricted export quotas of the metals with no official explanation, immediately sparking debate over decentralization of world rare earth production.

Great quantities of rare earth ores are known in California, but current mining is not significant enough to strategically control any portion of the global rare earths market.
Rare earths are traded on the NYSE in the form of ETFs that represent a basket of supplier and mining stocks, as opposed to trading in the metals themselves. This is due to their rarity and price, as well as their almost strictly industrial consumption. Rare earth metals are not considered a good physical investment like precious metals, which hold low-tech intrinsic value.

Rare Earth Metals and Their Applications

In order of increasing atomic mass, the rare earth metals and some of their common applications are given below.

  • Scandium: Atomic weight 21. Used to strengthen aluminum alloys.
  • Yttrium: Atomic weight 39. Used in superconductors and exotic light sources.
  • Lanthanum: Atomic weight 57. Used in specialty glasses and optics, electrodes and for hydrogen storage.
  • Cerium: Atomic weight 58. Makes an excellent oxidizer, used in oil cracking during petroleum refining and is used for yellow color in ceramics and glass.
  • Praseodymium: Atomic weight 59. Used in magnets, lasers and as green color in ceramics and glass.
  • Neodymium: Atomic weight 60. Used in magnets, lasers and as purple color in ceramics and glass.
  • Promethium: Atomic weight 61. Used in nuclear batteries.
  • Samarium: Atomic weight 62. Used in magnets, lasers and for neutron capture.
  • Europium: Atomic weight 63. Makes colored phosphors, lasers, and mercury-vapor lamps.
  • Gadolinium: Atomic weight 64. Used in magnets, specialty optics, and computer memory.
  • Terbium: Atomic weight 65. Used as green in ceramics and paints, and in lasers and fluorescent lamps.
  • Dysprosium: Atomic weight 66. Used in magnets and lasers.
  • Holmium: Atomic weight 67. Used in lasers.
  • Erbium: Atomic weight 68. Used in steel alloyed with vanadium, as well as in lasers.
  • Thulium: Atomic weight 69. Used in portable x-ray equipment.
  • Ytterbium: Atomic weight 70. Used in infrared lasers. Also, works as a great chemical reducer.
  • Lutetium: Atomic weight 71. Used in specialty glass and radiology equipment.