Praseodymium


Auer von Welsbash was the first scientist to isolate the didimia, in 1885, by fractional crystallization of the double ammonia nitrates of two new elements. It was thought at the time that didimia was a simple element. However, Welsbash proved that this substance was a neodymium and praseodymium mixture. Its name derives of the greenish color of the respective salts.