If you look at earrings, there will be words on them. There are several words printed on it. Generally, S925 is silver, AU750 is 18K gold, and PT950 is platinum.
If it is inlaid with natural diamonds or natural gems, there will also be lettering, such as D0. 1 1ct, indicating that the diamond is 1 1.
If it is not printed, it is not jewelry, only jewelry or handicrafts.