Like silver, bronze will eventually darken, although most of our bronze jewellery contain a ceramic coating to prevent/delay oxidation. Bronze that oxidizes darkens in color which gives the metal a beautiful, antique touch. Normally, darkening happens evenly, but cosmetics or chemicals can cause other (including green) effects. When your bronze gets darker, you can wipe it clean with a flannel cloth, possibly with a damp cloth with a little ecological detergent. Bronze is a hard metal, it will not bend easily but rather break when a lot of force is applied to it.