Judging from the picture, you should buy a pure gold ring. In fact, this kind of thing, as long as it is commonly encountered by jewelry companies, is basically not a quality problem. You don't have to worry. You can think about whether you have touched anything else. Generally, this situation basically belongs to the chemical reaction caused by the wearer's careless contact with other things. Of course, don't get excited when you hear the chemical reaction. How do you think that's possible? In fact, everyone in our life will come into contact with it every day, such as hand sanitizer or facial cleanser.

Actually, don't worry, just go to Chow Tai Fook's store for maintenance.