Symmetry, like polish, is a factor which refers to the skill and craftsmanship of the diamond cutter, and which has a direct affect of the diamonds brilliance and its "cut" grade. Excellent symmetry ensures maximum brilliance and sparkle because it increases the duration and intensity of the reflected light rays within the diamond. Symmetry lower than good effect the visible appearance of the diamond, and can affect the price accordingly. In general,
The major factors which affect the symmetry of the diamond are as follows:
- Roundness of the girdle.
- Centricity of the culet under the table facet.
- Alignment of the crown facets with the pavilion facets.
- Parallelism of the table facet to the girdle plane.