COPPERAS

copperas. Copperas, n. a solution of iron in sulphuric acid

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Cop″per‐as (?), n. [[OE. coperose, F. couperose, fr. (assumed?) L. cuprirosa, equiv. to G. χάλκανθοσ, i.e. copper flower, vitriol. See Copper and Rose.]] Green vitriol, or sulphate of iron; a green crystalline substance, of an astringent taste, used in making ink, in dyeing black, as a tonic in medicine, etc. It is made on a large scale by the oxidation of iron pyrites. Called also ferrous sulphate. ☞ The term copperas was formerly synonymous with vitriol, and included the green, blue, and white vitriols, or the sulphates of iron, copper, and zinc.