rare earths

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rare earths,

in chemistry, oxides of the rare-earth metalsrare-earth metals,
in chemistry, group of metals including those of the lanthanide series and actinide series and usually yttrium, sometimes scandium and thorium, and rarely zirconium. Promethium, which is not found in nature, is not usually considered a rare-earth metal.
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. They were once thought to be elements themselves. They are widely distributed in the earth's crust and are fairly abundant, although they were once thought to be very scarce. Generally, the name of an earth is formed from the name of its element by replacing -um with -a; e.g., the earth of cerium is ceria. Mixed rare earths are used in glassmaking, ceramic glazes, glass-polishing abrasives, carbon arc-light electrode cores, and catalysts for petroleum refining. Individual purified rare earths have many uses, e.g., in laser, fiber-optic transmission amplifiers, and night-vision goggles. Important rare-earth minerals include bastnasite, cerite, euxenite, gadolinite, monazite, and samarskite.
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References in periodicals archive ?
said earlier this year that it would look to Australia and Canada to develop rare earths reserves around the world to reduce the global reliance on China.
Worldwide, many mines have around six percent or less rare earths in their ore.
In the next five years, Xiamen Tungsten Industry has determined the strategic positioning of tungsten and rare earth as the main industry, with energy new materials and molybdenum series products as the two wings, and real estate as a profit.
The capital raising comes on the heels of a successful feasibility optimisation program, guided by rare earth company and Greenland Minerals major shareholder Shenghe Resources Holding Co Ltd, that resulted in a 40% reduction in both capital and operating cost estimates.
In return, Beijing raised tariffs on $60 billion of American goods and hinted at banning rare earths exports to the US.
As monazite is an important source of rare earth elements and contains thorium, a naturally occurring radioactive metal, monazite was considered an important national defense resource.
China produced 120,000 MT of rare earths in 2018, up from 105,000 MT the previous year.
Also, reporting solely on mined rare earths or purified oxides distorts government policy decisions because these materials have no significant technology or defense application until they are refined into metals.
The assets subject to this transfer consist mainly of a business sector which conducts R&D in Chichibu Plant as a part of the Showa Denko Group's rare earth magnetic alloy business and SDK's intellectual property rights on rare earth magnetic alloys.
Despite their collective name, the rare earths aren't all that rare in terms of availability in the earth's crust.
On the other hand, the mining and production of rare earths is hazardous, (22) and some countries like the United States and Australia have stopped domestic production.