Our jewelry can only chemically change colour when it comes into contact with another substance. It can't change colour solely by oxidation. We recommend that you do not spray perfumes directly onto it or other everyday products like creams, tans, lotions, hand antibacterials, etc., containing harsh chemicals that can destroy the plating. If your jewelry comes in touch with any of the above, clean it gently with warm soapy water and gently wipe it dry with a soft cloth after each wear.