AGS Laboratories has announced that it will start issuing a cut grade for princess-cut diamonds by the end of the first quarter of 2005. It will be followed by the new round-brilliant cut-grade system to be released in the second half of 2005. The science supporting the new cut-grade system reflects AGS Laboratories’ advancement from a proportion-based to a performance-based cut-grade system.

In the new cut-grade system, all 58 facets of a diamond are measured in three dimensions rather than two. The measurements are used by a ray tracing computer program to trace light rays traveling through a diamond. The program shows the quantity and quality of the light being returned to the viewer. In addition to proportion, symmetry, and polish, AGS Laboratories will also consider brightness, dispersion, leakage, contrast and spread in assigning the final cut grade.

The zero cut parameters for the traditional 53 percent to 57 percent tables have been tightened. These advancements in proportion grading eliminate a certain percentage of the original combinations of the round brilliant AGS 0 cut grade. Therefore, some diamonds that were previously AGS 0 cuts will no longer meet the new scientific standards, because of lower scores in the light performance categories.

The science supporting the refinement and realignment of the round brilliant AGS 0 cut-grade system adds additional table sizes, but only in combination with very limited relationships of angle and facet configuration. To assist clients in cutting to the new standards, AGS Laboratories will issue parameter guidelines for the princess cut and will issue the new round-brilliant parameters in the first half of next year.

For more information, call (702) 233-6120 or visit www.agslab.com.