- 1). Use paper towels, warm water and liquid dish soap to clean the entire copper surface of the item you want to treat. If it is an older copper object, you'll mostly be cleaning dirt and dust. If it's brand new, you should clean it anyway. Commercial copper products are often treated with a thin coating of oil before they're shipped, and if this coating is left in place, this patina procedure won't work.
- 2). Rinse all soap suds off of the copper with clean water and dry the piece well with paper towels.
- 3). Mix up a strong solution of salt water in a plastic spray bottle. If you live near the ocean, you can just gather your salt water naturally. Otherwise, pour 1/2 cup of salt into the 12 to 24-ounce bottle of water gradually, shaking the bottle well to mix it up until the salt grains no longer dissolve in the solution.
- 4). Spray the copper item well with the salt water mixture. Do not touch, wipe or dry the salt water. Allow it to air dry naturally.
- 5). Repeat step four as many times as you see fit. With each salt water application, more and more patina will develop. You can stop whenever the copper reaches the stage you have in mind.
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