A diamond’s CUT not only refers to its shape, but also how effectively the stone can return light back to the viewer’s eye. A well-cut diamond will appear very brilliant and fiery, while a poorly cut stone can appear dark and lifeless.

Diamonds are renowned for their ability to transmit light and sparkle so intensely. The cut grade is all about how well a diamond’s facets interact with light. Precise artistry and workmanship are required to fashion a stone so its proportions, symmetry, and polish deliver the magnificent return of light only possible in a diamond.

The cut grade also takes into account the design and craftsmanship of the diamond, including its weight relative to its diameter, its girdle thickness (which affects its durability), the symmetry of its facet arrangement, and the quality of polish on those facets.

Polish is the overall condition of the surfaces of a finished diamond. Polish is rated Good (GD), Very Good (VG), Excellent (EX), and Ideal (ID).

Symmetry refers to the precision of the shape and arrangement of facets in a diamond. Although to the naked eye finish features only have a tiny effect on appearance, symmetry is an significant aspect.

Read about diamond color

gia cut scale


Diamonds are cut in many different shapes. The common shapes that are well known to all include: Round, Asscher, Emerald, Oval, Marquise, Pear, Radiant, Princess, and Heart.