n. Symbol Co
A hard, brittle metallic element, found associated with nickel, silver, lead, copper, and iron ores and resembling nickel and iron in appearance. It is used chiefly for magnetic alloys, high-temperature alloys, and in the form of its salts for blue glass and ceramic pigments. Atomic number 27; atomic weight 58.9332; melting point 1,495°C; boiling point 2,927°C; specific gravity 8.9; valence 2, 3. See Periodic Table.
[German Kobalt, from Middle High German kobolt, variant of kobold, goblin (from silver miners' belief that cobalt had been placed by goblins who had stolen the silver); see KOBOLD.]
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