What is Praseodymium?

The compound didymium was discovered by chemist Carl Mosander in 1841. It took a further 44 years before the elemental twins, praseodymium and neodymium, were finally separated. Praseodymium is a soft, silvery, malleable and ductile metal, valued for its magnetic, electrical, chemical, and optical properties. It is too reactive to be found in native form, and pure praseodymium metal slowly develops a green oxide coating.

Properties

  • Atomic Symbol: Pr
  • Atomic Number: 59
  • Element Category: Lanthanide metal
  • Atomic Weight: 140.90765

History

Praseodymium was identified as a separate element in 1885 by chemist Baron Carl Auer von Welsbach, at Heidelberg, when he successfully split the compound didymium into its two components, neodymium and praseodymium. The less abundant new earth was named praseodymium, from the Greek prasios didumous, meaning green twin.

Uses

  • In combination with neodymium, praseodymium is predominantly used in neodymium magnets used in a growing arena of high-tech applications.
  • Praseodymium and neodymium oxides are used in welder and glass blower goggles to protect the eyes from yellow flare and UV light.
  • Vibrant yellow ceramic tiles and dinnerware, popular in the Mediterranean region, are the result of combining praseodymium and zirconium oxides.
  • Praseodymium oxide is a catalyst to make the most widely used plastic, polyethylene, for soda bottles, bubble wrap, food plastic wrap, sandwich bags and milk cartons.

Sources

Praseodymium occurs in the Earth’s crust at an average concentration of 8 parts per million.

Praseodymium is commonly found in carbonatites in the mineral bastnäsite. Bastnäsite deposits in China and the United States constitute the largest percentage of the world’s rare earth economic resources.

The second largest host of praseodymium in economic deposits is the mineral monazite, the main host mineral at Yangibana. Monazite deposits occur in Australia, Brazil, China, India, Malaysia, South Africa, Sri Lanka, Thailand, and the United States in palaeoplacer and recent placer deposits, sedimentary deposits, veins, pegmatites, carbonatites, and alkaline complexes. Praseodymium sourced from the LREE-mineral loparite is recovered from a large alkali igneous intrusion in Russia.