Metal must be free of oil, lacquer, grease, wax, dirt and grime; oxidation on metal is fine (actually preferred). Apply the Green Patina with a stiff bristle brush to copper, brass or bronze. Stipple it on the metal with a brush. Apply a thin coat. Do not continue to “play” with the Jax Green Patina after application. Do not rinse off it off the metal. Walk away. Allow 24 hours to dry. Reapply up to 3 coats allowing 24 hours in between coats. We would also consider the use of one of the Jax Darkeners (our preference would be Jax Brown-Black) before you apply the Jax Green Patina. It will be far more authentic than just applying the green on top of virgin copper.