With the release of the new cut grading systems, one disappointment for me personally was that neither GIA or AGS include a grade for optical symmetry. If you take note on each of the round brilliant cut diamonds in our inventory, including some square shapes, we assign a grade for "Optical Symmetry".

Let's expound a bit so you can learn about this feature which we deem as very important with regards to cut grading and analysis.

Optical Symmetry relates directly to the subject of craftsmanship. Ie. The care and precision to which the cutting factory took when producing their product. Within the realm of AGS Ideal or GIA Excellent cut qualities these diamonds would include but are not limited to the Hearts and Arrows types of diamonds you see on this site and others who carry this kind of product. Another expression for Optical Symmetry could properly be termed 3 dimensional symmetry and is to be distinguished from traditional symmetry grading

In an earlier chapter you read and saw the factors that impact traditional symmetry grading which primarily concerns itself with an analysis of the exterior and how the facets meet and are aligned on the diamond. Optical symmetry, while considering the exterior facet surfaces focus' more so on facet alignment on a 3 dimensional scale as we peer into the dimension of the stone. A diamond is, after all, a 3 dimensional object. There are 3 specific scopes which we utilize to determine an optical symmetry grade.

The Hearts & Arrows viewer
DiamXray
Ideal-Scope®

We'll step you through the process and compare some stones.

The "Superior" Optical Symmetry grade

Diamonds that exhibit "Superior" optical symmetry must display a perfect optical alignment of the facets when observing the internal reflections of the stone. While each of these diamonds vary in their optical properties, each are cut to a very extreme level of precision.

Crown View (H&A viewer)	Pavilion View (H&A viewer)	DiamXray View