Rare Earth Minerals & Metals

Abstract

The rare earth elements are the group of 15 chemically similar elements with atomic numbers between 57 and 71 inclusive: lanthanum, cerium, praseodymium, neodymium, promethium, samarium, europium (together making up the light’ or ‘cerium’ subgroup), gadolinium, terbium, dysprosium, holmium, erbium, thulium, ytterbium and lutetium (which together with yttrium, not itself a rare earth element but invariably associated with them in nature, make up the ‘heavy’ or ‘yttrium’ subgroup).