Lutetium (Lu)


  • Symbol: Lu
  • Atomic Number: 71
  • Atomic Weight: 174.9668
  • Element Classification: Lanthanide
  • Discovered By: Georges Urbain; independently by Carl Auer von Welsbach
  • Discovery Date: 1907
  • Name Origin: Named after Lutetia, the Latin name for Paris
  • Density(g/cc): 9.841
  • Melting Point: 1663°C
  • Boiling Point: 3402°C
  • Appearance: Silvery-white, hard, and dense metal
  • Atomic Radius(pm): 174


Lutetium was independently discovered in 1907 by French chemist Georges Urbain and Austrian scientist Carl Auer von Welsbach. Both scientists identified lutetium as a new element while studying the mineral ytterbia, previously thought to be a pure compound but later found to contain at least two elements. Urbain and Welsbach proposed different names for the element, but Urbain’s name, lutetium, derived from the Latin name for Paris, was eventually adopted by the International community.

Relation to Other Elements

Lutetium is the last member of the lanthanide series, a group of elements known for their similar chemical properties and inclusion in the rare earth metals. It exhibits typical characteristics of lanthanides, such as forming trivalent ions and having similar ionic radii. Lutetium is often considered a bridge between the lanthanides and the transition metals due to its unique electronic configuration, which results in the highest density, melting point, and hardness of the lanthanides.

Natural Occurrence

Lutetium is one of the least abundant and most expensive of the rare earth metals. It is not found free in nature but occurs in small amounts in various minerals, including monazite and bastnasite, alongside other rare earth elements. The extraction and purification of lutetium from these minerals require extensive separation processes due to its similar chemical properties with other lanthanides.


Lutetium has a few specialized applications:

  • Catalysis: Lutetium is used as a catalyst in various petrochemical processes, including the alkylation, hydrogenation, and polymerization of hydrocarbons.
  • Medical Imaging and Therapy: Lutetium-177 isotopes are used in targeted radionuclide therapy and PET scan imaging for treating certain types of cancer and neurological conditions.
  • Electronics: Lutetium is utilized in the manufacturing of phosphors for LED lights and other display technologies.
  • Research: Due to its unique properties among lanthanides, lutetium is used in scientific research, including studies in materials science and high-energy physics.

The discovery of lutetium filled the last spot in the lanthanide series, providing valuable insights into the properties and behaviors of rare earth elements. Despite its scarcity, lutetium’s applications in catalysis, medicine, and technology demonstrate the ongoing importance of even the least abundant elements in advancing scientific and industrial developments.

Ytterbium (Yb)

Hafnium (Hf)