Any of a large class of chemical elements including scandium (atomic number 21), yttrium (39), and the 15 elements from 57 (lanthanum) to 71 (see lanthanides). The rare earths themselves are pure or mixed oxides of these metals, originally thought to be quite scarce; however, cerium, the most plentiful, is three times as abundant as lead in the Earth's crust. The metals never occur free, and the pure oxides never occur in minerals. These metals are similar chemically because their atomic structures are generally similar; all form compounds in which they have valence 3, including stable oxides, carbides, and borides.
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Wipo Publishes Patent of Hitachi, the Foundation for the Promotion of Industrial Science for "Apparatus and Method for Recovering Rare Earth Metal from Rare Earth Magnet" (Japanese Inventors)
Sep 18, 2012; GENEVA, Sept. 18 -- Publication No. WO/2012/121353 was published on Sept. 13. Title of the invention: "APPARATUS AND METHOD FOR...
Agency Reviews Patent Application Approval Request for "Method for Producing Surface-Modified Rare Earth Metal-Based Sintered Magnet"
May 14, 2013; By a News Reporter-Staff News Editor at Life Science Weekly -- Hitachi Metals, Ltd. has been issued patent application serial...