Although colored silver will not fade, it will also be oxidized. This is because the glaze on the surface of colored silver jewelry can't completely cover the silver tire, so the exposed place of silver edge is easy to be oxidized (silver is easy to be oxidized when it meets air, so colored silver jewelry should not be directly exposed to air as far as possible), and the oxidized silver edge will appear yellow and black.
Generally speaking, if you buy good colored silver, the appearance is not easy to fade, but it does not rule out that there will be some colored silver ornaments with poor workmanship on the market. So if you want to buy colored silver jewelry, you'd better go to a brand store, which also has after-sales service.