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Triple Zero Diamond Cut Technology Will Bring New and Unique Designs Of Diamond

2005: Triple Zero Diamond Cut Technology Makes the Diamond More Clear

August 2005

The Gemological Institute of America will begin issuing new grading reports with a diamond cut grading grade January 1, 2006. The grade will be included on diamonds in the GIA D-to-Z range and Flawless-to-I3 clarity range. The news was announced at a press conference at the Waldorf-Astoria during the JA show, which was attended by the Diamond Registry.

What is interesting is that this report does not change the way any of the Cs most familiar to the public — color and clarity — are graded. It simply gives a grade for an additional “C.”

Today, the only way to see if your diamond is well-cut is to go by the AGS Triple-Zero system, which is based on the Ideal Cut. What GIA has said is that the Ideal Cut is not the only beautiful cut out there — that different sets of proportions can yield an equally beautiful stone. They have devised a system that allows a lot more room for individual taste than the AGS’ system does. Stones that receive the top grade of “excellent” in the GIA system that wouldn’t get that grade from AGS.

The implementation will be difficult because there are tens of thousands of stones without a cut grade, and it’s possible they are already going to come flooding back. At a seminar at the Diamond Dealers Club, Tom Yonelunas of the GIA said the lab had hired more people to deal with some of the expanded load. GIA also has a free re-issue service for diamonds graded between August 1 and Dec. 31, 2005 without the diamonds being resubmitted. For round diamonds graded in 2005, prior to August 1, only a small portion of diamonds will be needed to return to the laboratory. But if the stones were graded prior to 2005 — and there are many of those out there — we assume that the stones will have to be returned.

Still, more work is more work, and the GIA has had its problems in the recent past, and we can’t see how this will help make things faster.

Here are some of the points about the new grade:

* The system is based on 3-D computer modeling and other predictive algorithms, which have been validated through observation testing, including more than 70,000 observations of actual diamonds by individuals at all levels of the trade.

* It does not apply to fancy color or fancy shape diamonds (see our AGS story on the next page for that), or round stones with different faceting arrangements.

* GIA considers the following seven components when assessing a cut grade: Brightness, fire, scintillation, weight ratio, durability, polish and symmetry.

* To get a sense of how the grade works, the GIA has developed the GIA Facetware Cut Estimator, online software that allows users to predict the cut grade of a round brilliant cut by entering its relevant parameters. It is available at

We will wait until we see exactly how the new grade works, but we are still a leery of a cut grade. Beauty is fundamentally in the eye of the beholder. The best way to see how a beautiful a diamond is to look at the Four C’s in total. For example, an I3 with an excellent cut grade will still be less beautiful than a VS stone with a good cut grade.

While GIA Does Rounds. AGS Does Fancies

At the recent JA show, the Diamond Registry spoke to Peter Yantzer, director of the AGS Lab, and Jim Caudill, director of the Advanced Instruments Division. While GIA is busy establishing a standard for rounds, they are busy trying to establish a standard for fancy cuts, beginning with the princess. They also refigured their round brilliant grade, so that their AGS zeroes (their highest grades) are given to more than just Tolkowsky Ideal cuts.

The difference is in standards. When GIA says that most of the diamonds they see will fall into the “very good” and “excellent” category, AGS says that only a small amount of diamonds will receive its top grade of zero. They are not aiming at everyone, like the GIA does, but only at the “premium” market where only certain manufacturers that specialize in cutting are good enough.

While the GIA evaluates seven factors in its cut grade, AGS evaluates 11 (brightness, contract, dispersion, leakage, weight ration, tilt, girdle thickness, culet size, durability, polish and symmetry.)

AGS is now trying to figure out cut grades for other fancy stones. Given that GIA followed AGS into round brilliant grading, we are sure the GIA is working on fancy grading too.

What Does This Mean For the Trade and Consumer?

It will certainly take a while for the industry to adjust to all these changes in the certification market, which has become more and more complex. It will take at least a year before all cutters become familiar with the new GIA cut grade, and will take even longer with the AGS’, which has even more variables.

The cutters will certainly switch to higher standards in cutting. Under the old system, many cutters looked only at final weight, sacrificing what everyone agreed were proper standards of good cutting along the way. Now, more cutters will conform to higher standards, because that means the stone will get a higher price.

On the other hand, the public should not be misled to think that only triple zero or excellent or very good stones are beautiful diamonds. Sometimes it’s worthwhile to sacrifice cut to get a better color, for instance, which is much more visible to the untrained eye. Every layman can see the difference a “D” color and a “J” color. But even the smartest and most intelligent consumer will have difficultly differentiating between “excellent” and “very good” cut stones. A big price differential, therefore, is not justified, but in the end the market will decide.

The winners will be the big companies. They will have the latest, most sophisticated machines like the Sarin and OGI and can train their cutters to cut to GIA’s specifications. Not all the small cutters can afford these devices.

And where does all this leave the jeweler? One owner of a small jewelry chain told the Diamond Registry that he is not worried about either cut grade. He is switching to one of the private laboratories which don’t have a cut grade and have far more lenient grading and appraisals (even though a recent Dateline NBC piece warned viewers against this.)Grade 1 Image


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