My suggestions are: first, you should go to a regular brand to buy jewelry. Secondly, when you buy it, you should ask if you have provided a certificate. Generally, jade articles have information about the products, including photos and ingredients. Diamonds will have a code (here refers to a slightly larger diamond with a score of more than 30 points). You can ask the clerk to provide a magnifying glass to see if the code on the diamond waist is consistent with the certificate. Pure gold depends on printing. For example, we often say that the printing of 18k gold jewelry is pd 750, and the printing of platinum is pt. Generally, the purity information such as pure gold printing or 999 is written on gold. Silver is S925, which means 925 silver ornaments. The lettering on jewelry has national standards, and jewelers can't type casually. Remember to ask for a formal invoice after purchase, which will write the composition information. You can check with words. This can be guaranteed and it is also evidence. If you buy a fake, you can complain.