If you want to clean a Button just dip it in a cereal bowl with enough Ammonia in it to cover the item. Depending on what type of soil it was found in, anywhere from 5 min. to several hours soaking will do it. It won't hurt the button. Any time you take a tooth brush to a button with gilt on it you lose some. I believe this is by far the best way to clean Buttons and all Gold Jewelry. If in doubt just try it first on a junk piece of brass that has gilt on it.