A full cut diamonds refers to a round brilliant diamond that is cut according to standard cut specifications. The standard cut for round brilliant diamonds contains 57 or 58 facets, strategically placed to enhance the light performance of the stone. Round brilliants, or full cut diamonds, are the classic diamond shape and account for over 75% of all diamonds.

You will sometimes come across round brilliant diamonds that contain a non-standard number of facets, often much lower than 57 or 58. Although these diamonds have the shape, they are not considered full cut diamonds as the number of facets do not match the standard.