The next c refers to how well the diamond has been cut. This evaluates the way each of the facets of the diamond interact with light. The cut of a diamond is given one of 5 possible grades.
2. Very Good
The ideal diamond has facets positioned at such an angle to reflect the light back into the gemstone. When a diamond is faceted perfectly a stone will display an optimum balance of internal reflections (brilliance), color dispersion (dispersion), and brightly colored flashes of reflected light(scintillation).