• Diamond cutting is the art and science of creating a gem-quality diamond out of mined rough. The cut of a diamond describes the manner in which a diamond has been shaped and polished from its beginning form as a rough stone to its final gem proportions.
  • There are mathematical guidelines for the angles and length ratios at which the diamond is supposed to be cut in order to reflect the maximum amount of light. Round brilliant diamonds, the most common, are guided by these specific guidelines, though fancy cut stones are not able to be as accurately guided by mathematical specifics.
  • The culet is the tiny point or facet at the bottom of the diamond. This should be a negligible diameter, otherwise light leaks out of the bottom. The modern round brilliant has 57 facets (polished faces), counting 33 on the crown (the top half), and 24 on the pavilion (the lower half).
  • The girdle is the thin middle part. The function of the crown is to refract light into various colors and the pavilion's function to reflect light back through the top of the diamond.