VITRIOL

any of certain hydrated sulfates or sulfuric acid. Most of the vitriols have important and varied industrial uses. Blue, or roman, vitriol is copper(II) sulfate pentahydrate; green vitriolalso called copperas, a name formerly applied to all the vitriolsis iron(II) sulfate. White vitriol is zinc sulfate; red, or rose, vitriol is cobalt sulfate; and uranvitriol is a native uranium sulfate. Oil of vitriol is concentrated sulfuric acid (q.v.).