Round diamonds are the ones that make up approximately 75% of all diamond purchases. Round brilliant cuts are preferred over fancy shapes as they have superior reflection of light which maximizes its potential for brightness. With 58 facets including the culet, it yields maximum shine as the cut naturally follows the rough diamond crystal. The early modern and brilliant round cut was created in 1919 and was known as the Tolkowsky cut named after its creator Marcel Tolkowsky, a diamond enthusiast and Russian mathematician.