Praseodymium Praseodymium was discovered in 1885 when it was separated from an earth called didymium . The earth was thought to contain a mixture of elements, and not a fundamental substance in its own right. Spectroscopic data of didymium yielded two absorption bands, one in the blue region and another in the yellow.
Praseodymium is a silvery white, fairly soft, malleable, and ductile metal.
It is moderately reactive in air, developing a green oxide coating that falls off to expose fresh metal for further oxidation . The metal is also quite reactive in water. Praseodymium is a rare-earth metal, and is also a member of the lanthanide series . Praseodymium is used as high-strength alloying agent in the magnesium used in parts of aircraft engines. It is an important alloying agent in steel.