Ideally, your container should be transparent so you can check on the appearance of your copper without having to open the container.
Don’t seal the bag all the way, or the air pocket will make it difficult to break the egg.
Wash the copper item afterward to remove any pieces of egg and to see what the item looks like when clean.
Warning: always wear rubber gloves and work in a ventilated area when handling ammonia. Safety glasses and a respirator mask are recommended. Be ready to wash your skin or eyes with running water for fifteen minutes in case of spills. To create a green patina, mix 2 cups (480 mL) white vinegar, 1. 5 cups (360 mL) pure non-detergent ammonia, and 0. 5 cups (120 mL) non-iodized salt. Mix in a plastic spray bottle until the salt dissolves. Use less salt to reduce the amount of green in the patina. [3] X Research source For a brown patina, mix baking soda in a spray bottle full of hot water until additional baking soda will not dissolve. [4] X Research source You may buy a commercial antiquing solution and follow the instructions on the packaging to achieve the desired color. Liver of Sulphur is commonly used for copper.
If you want to have more control over exactly where and how the patina forms, scrub with a scotch brite pad, brass brush, or cotton swab after spraying. [5] X Research source Wear gloves and safety glasses for this if your solution contains ammonia, acids or other dangerous chemicals. If you are in a low humidity area, place a plastic bag or sheet over the item to keep in moisture. Use a frame or drape it between larger objects so the plastic does not come in contact with the copper. [6] X Research source
Warning: always wear gloves and safety glasses when handling ammonia. Do not use the container that held ammonia to hold food or water. The more salt you use, the more noticeable the color will be.
