Don't trust the words on the jewelry. Those are all laser printed. I'll give you two methods: 1. If there is lettering, ask the other party to take out the certificate issued by the National Jewelry and Jade Quality Supervision and Inspection Center for this piece of jewelry. If the pictures are consistent, see if the inspection code of the inspection center is attached to the jewelry. 2. Take it to the quality inspection station for testing. There is an instrument called precious metal detector for detecting the purity of jewelry, which can measure the purity.