NEODYMIUM

(n.) A rare metallic element occurring in combination with cerium, lanthanum, and other rare metals, and forming amethyst-colored salts. It was separated in 1885 by von Welsbach from praseodymium, the two having previously been regarded as a single element (didymium). It is chiefly trivalent. Symbol Nd; at. wt. 144.3.