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Thulium

Lanthanide
Atomic Mass
168.93 u
Density
9.32 g/cm³
Melting Point
1,545 °C
Boiling Point
2,545 °C
State
Solid
Discovery
1879

Discovery

Discovered by Per Theodor Cleve in 1879.

Common Uses

  • Used in portable X-ray machines.
  • Used in medical treatments, such as the treatment of cancer.
  • Used in high-power lasers and phosphors.

Interesting Facts

  • Thulium is the least abundant of the rare earth elements.
  • It has a unique blue color when it is ionized, making it useful in specialized lasers.
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