GIA to implement its diamond cut grading system on Jan. 1

The Gemological Institute of America said today that it will begin issuing new grading reports on Jan. 1, 2006. For round brilliant cut diamonds in the GIA D-to-Z color range and Flawless-to-I3 clarity range, the new reports will include a Cut grade to accompany the Color, Clarity, and Carat Weight information that has been the core of the International Diamond Grading System developed by the Institute more than 50 years ago. GIA is allowing a lead time of Aug. 1 to Dec. 31, 2005 to give the industry time to study the new system.

The GIA Laboratory has been collecting proportion information on most of the round brilliant diamonds it has graded since Jan. 1. It will offer a free reissue service for reports on diamonds graded between Aug. 1 and Dec. 31 without requiring that the diamond be sent back to the GIA Laboratory. For round brilliant diamonds graded in 2005 prior to Aug. 1, there will be a nominal fee to reissue the reports and only a small portion of these diamonds will need to be returned to the laboratory for updated measurement information.

The addition of a cut grade to the GIA Diamond Grading Report and GIA Diamond Dossier for round brilliant diamonds is the result of more than 15 years of research and testing, including sophisticated computer modeling and ray tracing of more than 38.5 million proportion sets, GIA said. Results from the computer modeling were validated by more than 70,000 observations of more than 2,300 diamonds by individuals from the trade and the public.

“Today we are proud to deliver to the industry, and the public, a truly comprehensive cut grading system for round brilliant diamonds,” GIA President William E. Boyajian said. “This system helps retailers better communicate the effects of cut on round brilliant diamonds and enables consumers to buy with even greater confidence. It also results in greater flexibility for manufacturers in obtaining the most value from their rough.”

During the implementation period, there are two ways for individuals to estimate a GIA Cut Grade. First, they can enter the applicable parameters into the free online version of the GIA Facetware Cut Estimator, which can be found at Second, those with optical measuring devices such as Sarin or OGI can purchase from the manufacturer a version of their software with the GIA Facetware Cut Estimator Database embedded, with which they can quickly and automatically estimate cut grades for round brilliant diamonds, as well as gain advice on polishing from rough and recutting.

“We have worked very hard to develop a cut grading system that is both scientifically sound and practical to use,” said GIA Laboratory CEO Thomas C. Yonelunas. “We want to make the transition to the new system as smooth as possible for individuals throughout the trade, which is why we decided to provide a substantial amount of lead time and all the tools necessary to learn about our cut grading system in advance of the new reports being issued.”

To further support the implementation of the cut grading system, GIA released:

*A standardized viewing environment, the GIA DiamondDock, which provides the optimal lighting for both assessing and displaying the cut quality of round brilliant cut diamonds.

* The GIA Multi-Purpose Gemological Reticle, which provides a way to measure the proportions of a diamond manually with a microscope.

* A brochure that explains the cut grading system and how the cut grade will be presented on GIA Laboratory reports.

GIA said it will continue its ongoing efforts to educate the industry about the cut grading system through presentations, seminars, and participation in panel discussions at major trade shows, cutting centers, and other locations around the world. GIA Education course materials will incorporate details on the new diamond cut grading system starting in 2006. For additional information about the GIA Diamond Cut Grading System and related materials, please visit

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