Flotation of rare earths from bastnasite ore / Флотация редкоземельных элементов из бастназитовой руды

In 1949 a large bastn8site deposit was discovered at Mountain Pass, Cal if. Subsequent development of the deposit made the Uni ted States the worl d's largest source of rare-earth minerals. Since 1965, bastnisi te, a f luocarbonate of the cerium-group metals, REFC03, has replaced monazite as the principal source of rare earths; in 1978 it accounted for more than ha l f of the world production (§_).3 Rare-earth a lloys and compounds are used in petroleum crac.kin.g catalysts, ductile iron and high-strength, lo..,..alloy (HSLA) steel production, high- energy pertn4lnent magnets, color tel evi si on pi cture tubes, glass polishing and decolorizing, and ceramics. <...>