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DeCS
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Descriptor English:
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Metals, Rare Earth
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Descriptor Spanish:
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Metales de Tierras Raras
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Descriptor Portuguese:
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Metais Terras Raras
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Synonyms English:
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Earth Metals, Rare
Rare Earth Metals
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Tree Number:
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D01.268.558
D01.552.550
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Definition English:
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A group of elements that include SCANDIUM; YTTRIUM; and the LANTHANOID SERIES ELEMENTS. Historically, the rare earth metals got their name from the fact that they were never found in their pure elemental form, but as an oxide. In addition they were very difficult to purify. They are not truly rare and comprise about 25% of the metals in the earth's crust. |
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Indexing Annotation English:
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GEN: prefer specifics
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History Note English:
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76; was NON MESH before 1976
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Allowable Qualifiers English:
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Record Number:
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8850
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Unique Identifier:
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D008674
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Occurrence in VHL:
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Similar:
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DeCS
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