Wanted for:

Being a metal used in airplane engines and being used to create special yellow glass goggles for weilders and glass blowers.


Praseodymium has 59 protons, 59 electrons, and 82 neutrons in its most common isotope. it is the 59th element of the periodic table, and has an atomic mass of 140.9.


Pr, or praseodymium comes from the Greek words "prasios didymos', meaning geen twin after its green crystals and its close similarity to neodymium.


Color- silver

Atomic mass- 140.9

Atomic number- 59

It is also a metal and is solid at room temperature with a density of 6.77 grams per cubic centimeter.

First arresting officer

Carl Auer von Welsbach was born in Vienna on September 1, 1858. In 1878, he went to the University of Vienna and studied math, chemistry, engineering physics, and thermodynamics. In addition to finding neodymium and praseodymium, he also invented the gas mantle and the lighting flint, which is still commonly used in cigarette lighters.

Report of first arrest

Praseodymium was discovered in 1885 by Carl Auer von Welsbach by crystalizing didymium and observing two different colored crystals that were formed: pink crystals which are neodymium, and green crystals which are praseodymium. These new elements replaced didymium on the periodic table.

Last seen

Praseodymium is found in group 6 of the periodic table, and is a part of the lanthanide series. It is not found freely in nature, but is found in some minerals, mainly monazite.

known associates

Praseodymium can make a compound with oxygen to make Pr2O3.


Praseodymium is ONLY stable in isotope 141Pr. Any other isotope is UNSTABLE and DANGEROUS.


"Praseodymium Element Facts / Chemistry." Chemicool. N.p., n.d. Web. 28 Oct. 2014.

Knapp, Brian J., and David Woodroffe. Potassium to Zirconium. Danbury, CT: Grolier Educational, 2002. Print.