There is no specific brand of diamond, and the value of diamond is determined by its own 4c, that is, size, color, clarity and cut. The higher the level of these four parameters, the higher the value. Secondly, it depends on the certificate. Generally speaking, diamonds with GIA international certificates are a little more expensive than those with domestic certificates, because GIA international certificates are more authoritative and generally will not be downgraded. However, the domestic certificates are not rigorous, and the certificates issued by some unknown testing institutions are often downgraded, so try not to consider them. Taobao's diamond craftsman shop specializes in ordering GIA diamond rings. Although they all work in jewelry stores, ordering on Taobao saves more than half of the money to buy diamond rings of the same quality.