If the picture, total mass, color and other information marked on the paper certificate are consistent with the physical objects found on the official website of the testing organization and the above information, it can basically be determined to be genuine. All inspection certificates are generally one thing and one certificate, generally not one inspection certificate for a batch of goods. Under normal circumstances, testing institutions will not issue false certificates. If a false certificate is issued, the testing institution needs to bear the corresponding economic compensation responsibility. If it is very expensive jewelry, you should find an authoritative testing agency to issue a certificate. The most authoritative diamond is GIA's certificate, and domestic testing institutions are divided into national inspection and provincial inspection. The higher the level, the greater the authority. Very expensive, you can ask the merchant for re-inspection at the time of purchase. Ordinary jewelry can be handled by ordinary testing institutions. I don't think it's necessary to buy it in a physical store. Many brand businesses have online stores. Some certificates are forged, mainly because merchants steal columns, and one certificate is multi-purpose, but it is generally flawed. Therefore, it is still necessary to look at the relevant certificates to determine the authenticity of the products.