The GIA does not grade radiant cut diamonds, or other fancy shaped diamonds, for cut grade. If you see a cut grade associated with an radiant cut diamond, it is a cut grade that the jeweler is assigning to the diamond themselves. While this is okay, you should always verify the cut a jeweler provides since they can make mistakes in determining the cut rating since they don’t have a certificate to rely on.
For these reasons, and because how well a diamond is cut is the most crucial factor in maximizing the beauty, you want to make sure you understand the ideal cut specifications. The table below serves as a general guideline for evaluating the cut of a radiant diamond.