Rare Earth Element Bearing Mineral Bastnasite, This fluorocarbonate mineral, Bastn?site (Ce, La, Y)CO3F, is the most productive global mineral source for rare earth elements. This mineral tends to contain abundant light rare earth elements (LREE) and very low proportions of heavy ones, and tends to be specifically high in cerium, lanthanum, yttrium, and neodymium. Three variations in nomenclature are used to describe a few common ranges in the metal portion of the solid solution series. These are bastn?site-(Ce), bastn?site-(Y), and bastn?site-(La)