REEs, also called rare earth metals or rare earth oxides, or lanthanides, are a set of 17 silvery-white soft heavy metals. The 17 rare earth elements are: lanthanum (La), cerium (Ce), praseodymium (Pr), neodymium (Nd), promethium (Pm), samarium (Sm), europium (Eu), gadolinium (Gd), terbium (Tb), dysprosium (Dy), holmium (Ho), erbium (Er), thulium (Tm), ytterbium (Yb), lutetium (Lu), scandium (Sc), and yttrium (Y). Scandium and yttrium are not part of the lanthanide family, but end users include them because they occur in the same mineral deposits as the lanthanides and have similar chemical properties. The term “rare ... (full story)