Rare earth minerals & metals

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). These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.