It’s accepted wisdom that cut is as important to a stone’s appearance as the other three Cs—sometimes more so. Yet there is no universally accepted system for grading cut and no grade at all from the biggest lab, The Gemological Institute of America’s Gem Trade Laboratory.
That may change. After a decade of research, GIA is coming forward with a cut grade—or something that might be a cut grade, depending on what the trade thinks. With characteristic caution, it’s not committing to anything more than putting the grade on reports next spring—a plan that GIA has announced, and not followed through on, before.
If it does happen, it will be the lab’s biggest change since it began issuing reports in 1955, and it could, like the GIA scales for color and clarity, give the trade a new “language” and way to look at diamonds—all of which increases the pressure on GIA to get it right.
“We certainly recognize the significance of the introduction of a global cut grade,” says Tom Yonelunas, CEO of the Gem Trade Lab. Yonelunas and GTL vice president Tom Moses plan seminars to let the trade know that something big is coming. “We know a change like this could be a little unnerving, a little uncomfortable,” Yonelunas says. “That’s why we are interacting with the trade so we can start the ball rolling and let people know this is going to happen.”
No details. So what exactly will happen? Details remain scarce, but the folks at GIA are planning to institute a cut grade system (and yes, they use the word “grade”) for white round brilliants only—not for fancy shapes or fancy colors, though that may come later. GIA will present the system in a way the trade and consumers can easily comprehend. Like the AGS cut grade system, it will be hierarchical, but unlike the AGS system, it won’t limit the top place to the Tolkowsky Ideal (although it will be in the top category.)
“There will be a significant number of proportions that fall into the upper grades,” says Moses. “Most of the diamonds that manufacturers believe are well-cut diamonds will fall into the top categories. This will be a liberating finding for manufacturers and ultimately for the retailer and consumer, because they will have more choices. Right now, many people are handcuffed by an old paradigm of cut.”
The new paradigm is a grade built from mini-grades, starting with the three factors that contribute to a diamond’s face-up appearance—brilliance (now called “brightness”), fire, and scintillation—calculated by GIA’s computer-generated metrics. The system also will consider the “physical aspects” of cut, such as a stone’s diameter-to-weight ratio, and durability—e.g., whether the diamond has a thin girdle edge that can be easily damaged. Then it will grade polish and symmetry, using the system already on reports.
“We have to look at cut in a different way than we have historically,” says Moses. “When you look at a diamond, there is a mosaic of things you see. Rather than look at proportions independently, we have to look at everything as interdependent. It is this interaction that determines how [diamonds] perform. Many cutters and polishers have understood that for a long time.”
Questions unsettled. Of course, many of these principles—particularly the rejection of “Ideal”—have been GIA dogma for some time now. GIA won’t talk about its newer plans, like what form the grade will take, saying nothing’s been finalized. But it pledges that when decisions are made, it will announce them as soon as possible.
“We will give the trade fair notice,” says Yonelunas. “As soon as we are comfortable with what we have, we will incorporate it into our communications. We have no intention of surprising people.”
If GIA is playing it coy for now, it’s because the new grade could have a huge impact. The trade might see reports without the grade as lacking, and manufacturers will resubmit stones to get the new information, resulting in a possible crunch for a lab that, at press time, was having one of its periodic backlogs.
Yonelunas says GIA has planned for this. Before the cut grade is rolled out, GTL will capture the information for it, so the reports will just have to be resubmitted and the grade calculated.
“All the client will have to do is return the original report from a certain point on, and we will replace it, and there will be a nominal charge,” he says. “So the good news is that it will not contribute to added time in the grading process.”
The new grade might also inspire cutters to redo their stones to get better marks. Manufacturers have asked GIA to let them know about the parameters quickly, so they can cut to them.
Moses says the research will ultimately be a boon for cutters, as it will help them get more economical yields from their diamonds. “One can envision working from a block piece of rough, and this will let you save material on the rough and also get you a higher grade with no extra weight cost,” he explains.
It also may add some new configurations to the mix. “In some cases, we had unusual proportions that led to interesting results,” Moses says. He predicts that some “unusual proportions today may not be unusual proportions in the future.”
Unprecedented. In the end, GIA is attempting something audacious: It’s developing a nomenclature for nothing less than beauty itself. For this reason, it has held observation tests to see if its computer calculations match what people actually see. To date, it’s collected 70,000 human observations of more than 2,000 diamonds from 350 observers.
“We wanted to [see whether], if the computer model predicted a diamond with high fire and brightness, a human observer agreed with that process,” says Moses. “[Originally] there was pretty good agreement, but not to a standard that we were satisfied with.” GIA realized lighting played a major role in how people observed stones, and from then on used a standardized lighting environment.
Yonelunas says the observation tests became critical to the study. “No theoretical model, no matter how intelligent we think it is, no matter how much thought was put into it, [would work] if it wasn’t perceived by tradespeople and non-tradespeople alike,” he says.
In fact, Yonelunas foresees a day when experienced diamond people will be able to estimate a stone’s cut grade just by looking at it. And, he notes, the new grade might settle one of the trade’s most contentious debates.
“We hear day in and day out that retailers lose sales because people were sold on a term or a number that can’t be backed up,” he says. “This will help [the trade] report and validate what they say and believe.”
“We are not talking about anything the trade doesn’t know,” adds Moses. “We are just putting the pieces together.”