Homemade Formula for Aging Metal - 1 cup of hydrogen peroxide, 1 cup of white vinegar and two tablespoons of salt. Put it in a spray bottle. This can be used on anything you want to create an aged patina...copper, brass, galvanized or steel.
Vinegar and Salt Patina Tutorial. Because homemade patina recipes can have unpredictable results, your vinegar and salt patina on copper may wind up being any shade of green, blue, turquoise – or possibly even something else!