A Quick Guide to Cleaning Bronze
The procedure for cleaning bronze can be different, depending on the object you are cleaning and its intended purpose. Some people may want to clean their bronze vases or metals until they are shiny, while antique bronze items you may want to retain a certain amount of discolor so that it has that antique appearance, but clean it enough so that it looks good.
One thing to keep in mind about cleaning bronze is when you are cleaning this metal you are really cleaning an object that is made of copper. A great number of bronze objects will contain 88% copper, and the rest is made up of tin. If you have an object that is made of 90% copper and the rest zinc, what you have is brass and not bronze. In any case, the procedure for cleaning bronze and brass are the same.
You can buy a number of commercial products that are meant for cleaning bronze; in most cases it will be the same products that are used for cleaning brass and copper as well. What you should be aware of is that the commercial cleaners are harsh and may actually damage the object while it is cleaning it. People who trade or collect bronze will often turn to a home remedy cleaner over the commercial cleaners due to the fact that there is less chance of causing damage to the object.
For cleaning bronze statues that are outdoors, the first thing you will want to do is remove the patina, which will oxidize and turn the bronze green. To do this, begin with a mixture of soap and water, but remember that you do not want enough soap in the water that it causes suds. Scrub down the statue with sponges and use small brushes to get into areas that are difficult to reach. Once you have cleaned the entire statue, you will then want to dry it with large towels, buffing the bronze until it shines. It is best not to let it air dry.
Once the statue is dry, apply a layer of wax to the surface; again you will need to use a toothbrush in order to get to those tiny places. You will not want to use a vehicle wax, but there is a wax that is commonly used by museums known as Renaissance Wax. If you would like to add extra protection to an outdoor bronze statue you can also apply a layer of Armor All, which is basically a liquid silicone. This will help to keep the statue shiny and beautiful for even longer.
If you are cleaning an antique statue you will not want to remove the patina; the reason being is that this will diminish the value of the piece. An antique that looks shiny and new will resemble a reproduction. To clean an antique you can either use soap and water, or a mixture of baking soda and lemon juice. This will clean the bronze without taking the patina off of it. You can let the mixture sit on the object for a few minutes, but not to long, as the baking soda could damage the metal if it is in contact with it for a long period of time.
In the case that the home remedy cleaners do not do an efficient job, you can always turn to a commercial cleaner, but test an area before using it to ensure it will not damage the metal.
Cleaning bronze is really not all that difficult, and is actually a lot easier than cleaning other types of metals, such as silver.