1, surface oxidation: long-term contact with skin grease, sweat and other substances, resulting in the formation of an oxide layer or dirt on the surface, in this case, you can gently wipe the surface with a soft brush or clean cotton cloth, or wash it with mild soapy water, then rinse it with clear water and dry it.
2. Surface damage: The surface of turquoise is scratched or bumped, resulting in damage to the surface protective layer. In this case, it is necessary to decide whether maintenance is needed according to the specific situation. It's just a slight scratch on the surface, which can be repaired with some jewelry polishing agent. The surface is badly damaged and needs to be repaired by a professional jeweler.