AGS Adds Trade-Only Cut Grade Guidelines to Web Site

In an effort to meet industry requests for accessible information regarding the new American Gem Society cut grade system, AGS Laboratories has launched a “trade only” secure section on its Web site, featuring the cutting-chart guidelines for the system and a presentation explaining the methodology behind it.

The secure section requires registration and is restricted to the trade. However, the main Web site, which is still open to the public, has been updated to feature basic information on the cut grade, such as an expanded Frequently Asked Questions section. It also provides images of the new documents.

The new cut grade system moves AGS from a proportions-based methodology to one based on performance. In the new system, all facets of the diamond are measured in three dimensions rather than two. The lab measures a diamond using a ray-tracing computer program that traces light rays traveling through a gem. The program shows the quantity and quality of the light being returned to the viewer. AGS Laboratories will now consider brightness, dispersion, leakage, contrast, and weight ratio, in addition to proportions, symmetry, and polish, when assigning a cut grade.

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