A vitriol is a metallic sulfate hydrate crystal. Vitriol is produced when metal is dissolved in sulfuric acid and evaporated. Although copper (specifically copper sulphate) is typically the metal associated with vitriol, other varieties exist as well.

Copper forms Blue Vitriol or "Copperas,"chemically Cupric Sulfate Pentahydrate

Iron akes Green Vitriol or Green "Copperas,", Ferrous Sulfate Pentahydrate.

Zinc makes White Vitriol, Zinc Sulfate Hexhydrate.