Vert De Gris

Verdegris is the common name for the chemical Cu(CH 3 COO) 2 , or copper(II) acetate.

It commonly occurs by the action of acetic acid when copper, brass or bronze is weathered and exposed to air or seawater over a period of time.

Its name comes from the Middle English vertegrez, from the Old French verte grez, an alteration of vert-de-Grice — verd (green), de (of), and Grice (Greece)— "green of Greece".