Facet Cutting styles

The round brilliant cut diamond is the most efficient in using the light that enters it in the best possible way. However, its 58 facet cut is used to great effect in other stone shapes also. They never quite manage to and never will give the greatest fire but the are ofter cut in shapes to make the best possible use out of its size from rough format, trying not to lose to much in the process of cutting.
These are called fancy shapes. The same terms used for the facets of these are used on the round brilliant also and the four most popular are Pear-shape, oval cut, Marquise or Navette cut and Heart shape cut. The other fancy cut shapes vary in facet number, some may only have the minimum number of facets which is 17 that are required.
Any stone that is not brilliant cut is given a grading deduction due to it loss of proper usage of light.