Fast-acting liquid used by gunsmiths and industry to blacken or antique brass, copper and bronze parts. Easy to apply with no dimensional change. Often used to mark cartridge cases to identify loads. Excellent for blackening name plates, plaques, castings, sculptures and other home, workshop and hobby uses. Color varies depending on alloy and can be highlighted if desired. Final appearance is enhanced by applying a clear coat finish, wax or oil. Features Fast-acting liquid used to blacken or antique brass, copper and bronze parts. Easy to apply with no dimensional change. Often used to mark cartridge cases to identify loads. Final appearance is enhanced by applying a clear coat finish, wax or oil.