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GIA's history is rich with research and discovery. In the 1950's, GIA created the International Diamond Grading System, and established the standards that revolutionized the diamond industry.

When I think back to that era of innovation, it is truly awe-inspiring. A lot has changed since then. But GIA's passion, integrity, and commitment to research remain the same.

I'm pleased to introduce the new GIA Diamond Cut Grading System. With advances in computer modeling, we have been able to unlock the mystery of diamond cut — arguably the most complex and contested of the 4Cs. After more than 15 years of research and discovery, GIA has developed a scientific way to assess — and predict — the cut quality in round brilliant cut diamonds.

The most exciting and reassuring conclusion of our research is that there is no single set of proportions that define a well-cut round brilliant diamond. Our research has shown that many different proportions can produce attractive diamonds.

GIA has also developed software that provides a method of estimating a cut grade — and a database that is embedded into a number of leading diamond measuring devices so that this estimation can be automated. As a result, manufacturers can plan and, in effect, predict cut grades, buyers can compare cut qualities, and retailers can communicate the effects of cut on round brilliant diamonds.

GIA's mission of ensuring the public trust in gems and jewelry is reflected in this international research undertaking. And reminiscent of GIA's early innovations, I believe we will set the standards for cut quality the way we have set them for color and clarity for more than 50 years.


Thomas M. Moses
Senior Vice President, GIA Laboratory and Research