Cut or make is possibly the most importat of the 4C's. At the Diamond Certication Laboratory of Australia two aspects of the cut are judged seperately, the finish grade and the proportions. When examining the finish grade, attention is paid mainly to possible symmetry deviations and facets. A good finish grade testifies to the workmanship of the diamond polisher.

The proportions, the realtionship between the various parts of the stone, determine the fire and brilliance of the diamond (brightness). If the proportions are not optimal this will effect the brilliance and fire. The main symmetry deviations are first judged on the basis of the objective measured data. For this purpose, a Sarin system is used. The results are then checked by visual examination with a loupe.