Diamond 4Cs Education

The original diamond 4Cs -- cut, color, clarity and carat weight, are the most important factors to identify a diamond's quality. In recent years, in order to emphasize the importance of "diamond certificate", people add it as the 5th C of a diamond.

The cut tells how well the angles and proportions are when a rough diamond is cut into a loose diamond. The cut determines the fire and brilliance of a diamond. The color refers to how much color presents in a white diamond. The clarity refers to the amount of inclusions and blemishes a diamond contains. If you are looking for eye clean diamonds ("eye clean diamonds" means their inclusions or blemishes can not be seen with the unaided eye), go for diamonds that are VS2 or better in clarity with certificates from GIA or AGS. The carat weight refers to the weight of a diamond, not the "size". For the same weight diamonds, deep cut ones usually have a smaller table and might look like smaller diamonds overall. On the other hand, shallow cut diamonds usually have a larger table, and might look like bigger diamonds. In this way, "bigger" does not necessarily mean "better," because the bigger table might reduce the fire of the diamond. Read more education about diamond cut.

The 4Cs determine the quality of a diamond, but how can we trust if the 4Cs told by the jeweler is the actual 4Cs of the diamond? That's why we need the certificate. Diamond certificates are issued by diamond grading labs. It is like the identification card (ID) of each diamond. The more reputable the diamond grading laboratory is, the more trustworthy its diamond certificates are. Unless you are an expert of diamond grading, never purchase a loose diamond without the certificate, especially for online diamond shopping.