Atomic Number: 60
Atomic Mass: 144.24 amu (atomic mass units)
Melting Point: 1010.0 C (1283.15 K, 1850.0 F)
Boiling Point: 3127.0 C (3400.15 K, 5660.6 F)
Number of Protons: 60
Number of Electrons: 60
Number of Neutrons: 84
Classification: Rare Earth Metal
Crystal Structure: Hexagonal
Density @ 293 K: 7.007 grams per cubic centimeter
The rare earth element neodymium was discovered by the German chemist Carl F. Auer von Welsbach in 1885. He separated this element and another rare earth metal, praseodymium, from a substance called didymium. The name of the element comes from the Greek “neos didymos” which translates as new twin.
Neodymium is a member of the lanthanide or lanthanoid series of rare earth elements within the periodic table. There is no naturally occurring source of pure metal neodymium. Instead, mineral ores containing a mixture of rare earth elements provide a plentiful source for the element. The extraction and purification of rare earth elements from mineral ores makes use of the solvent extraction and ion exchange processes. Neodymium’s principal ore is monazite sand, which, in addition to many of the rare earth elements, also contains the highly radioactive element thorium. The presence of thorium means that the extraction process of the rare earth elements from monazite sand requires appropriate safety precautions.
Naturally occurring neodymium contains seven different isotopes. In order of their abundance, these are neodymium-142 (27.2%), neodymium-144 (23.8%), neodymium-146 (17.2%), neodymium-143 (12.2%), neodymium-145 (8.3%), neodymium-148 (5.7%) and neodymium-150 (5.6%). Two of these naturally occurring isotopes are unstable but they both have extremely long half-lives. Neodymium-144 decays by alpha decay and neodymium-150 decays by double beta decay. A number of other unstable isotopes of neodymium have been discovered with mass numbers ranging from 126 to 161. Neodymium-157 and neodymium-158 have the shortest half-lives at about 300 nanoseconds.
Neodymium has a number of valuable industrial applications.
* It makes up 18% of misch metal (a rare earth metal alloy used in the manufacture of cigarette lighter flints).
* Neodymium is a component of didymium glass, which is used to make welders and glass blowers safety goggles.
* When added to molten glass during processing it can remove the green coloration left by any iron contamination.
* Various neodymium compounds are used to impart a violet, gray or red color to glass. Astronomers use such neodymium containing glass to calibrate spectrometers.
* Artificial rubies made using neodymium are of use in laser technology.
* Some neodymium salts are used to color ceramics and enamels.
National Nuclear Data Center
The Los Alamos National Laboratory (Chemical Division)