According to the inquiry of Zhong Rui, Encyclopedia.com, the coated pearls will begin to fall off after two years of wearing, and they should be professionally maintained every year. If it is not maintained, the film will fall off after six months to one year. Pearls will oxidize or turn black when worn for a long time, and can be sent to a professional jewelry store for polishing. Coated pearls should not be exposed to chemicals, such as washing hands and bathing.