Copperas

02319 Cop"per*as (?), n. [OE. coperose, F. couperose, fr. (assumed?) L. cuprirosa, equiv. to G. grk cha`lkanqos /grk , 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 altname ferrous sulphate /altname . note &hand; The term copperas was formerly synonymous with vitriol, and included the green, blue, and white vitriols, or the sulphates of iron, copper, and zinc. /note