17 Rare Earth Metals

The seventeen rare earth elements, or rare earth metals, their atomic number and symbol, the etymology of their names, and their main usages is provided below:

21
Sc
Scandium
from Latin Scandia (Scandinavia), where the first rare earth ore was discovered.
Aluminium-scandium alloy

39
Y
Yttrium
for the village of Ytterby, Sweden, where the first rare earth ore was discovered.
YAG garnet, YBCO high-temperature superconductors

57
La
Lanthanum
from the Greek "lanthanon", meaning I am hidden.
High refractive index glass, flint, hydrogen storage, battery-electrodes, camera lenses, fluid catalytic cracking catalyst for oil refineries

58
Ce
Cerium
for the dwarf planet Ceres.
Chemical oxidizing agent, polishing powder, yellow colors in glass and ceramics, catalyst for self-cleaning ovens, fluid catalytic cracking catalyst for oil refineries

59
Pr
Praseodymium
from the Greek "praso", meaning leek-green, and "didymos", meaning twin.
Rare-earth magnets, lasers, green colors in glass and ceramics, flint

60
Nd
Neodymium
from the Greek "neo", meaning new-one, and "didymos", meaning twin.
Rare-earth magnets, lasers, violet colors in glass and ceramics, ceramic capacitors

61
Pm
Promethium
for the Titan Prometheus, who brought fire to mortals.
Nuclear batteries

62
Sm
Samarium
for Vasili Samarsky-Bykhovets, who discovered the rare earth ore samarskite.
Rare-earth magnets, lasers, neutron capture, masers

63
Eu
Europium
for the continent of Europe.
Red and blue phosphors, lasers, mercury-vapor lamps

64
Gd
Gadolinium
for Johan Gadolin (1760–1852), to honor his investigation of rare earths.
Rare-earth magnets, high refractive index glass or garnets, lasers, x-ray tubes, computer memories, neutron capture

65
Tb
Terbium
for the village of Ytterby, Sweden.
Green phosphors, lasers, fluorescent lamps

66
Dy
Dysprosium
from the Greek "dysprositos", meaning hard to get.
Rare-earth magnets, lasers

67
Ho
Holmium
for Stockholm (in Latin, "Holmia"), native city of one of its discoverers.
Lasers

68
Er
Erbium
for the village of Ytterby, Sweden.
Lasers, vanadium steel

69
Tm
Thulium
for the mythological land of Thule.
Portable X-ray machines

70
Yb
Ytterbium
for the village of Ytterby, Sweden.
Infrared lasers, chemical reducing agent

71
Lu
Lutetium
for Lutetia, the city which later became Paris.
Metal alloys