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What’s Your Type?

Like a pretty girl who steals the spotlight from her friends, type IIa diamonds seem to have stolen the headlines of the diamond business.

By Ettagale Blauer
Ask anyone in the industry about diamonds and you’re more likely to get a discussion of the 4Cs than the gemology of diamond types. As the science that identifies and classifies gemological differences among diamond types becomes more sophisticated, more technical characteristics are being used to describe diamond types and refine those descriptions. That, in turn, helps drive the demand and, ultimately, the price for diamonds that meet buyer preferences.
The Four Types
   Scientifically, all diamonds fall into one of four types: Ia, Ib, IIa and IIb. According to John King, chief quality officer of the Gemological Institute of America (GIA), an absolutely perfect diamond, “its carbon atoms regularly arranged in an evenly spaced lattice,” is theoretically possible, but highly unlikely. Most natural diamonds, he says, “have a number of structural anomalies and chemical substitutions.”
   Chief among these is the presence of nitrogen. When scientists sort diamonds into type I and type II categories, they do so based on the presence or absence of nitrogen.
   Type I diamonds, 98 percent of all diamonds, contain some nitrogen. These diamonds are further designated as either type Ia or Ib, depending on how the nitrogen atoms were formed during the growth process.
   According to the GIA, “the complex process of nitrogen incorporation in diamond takes place over geologic time scales at high pressures and high temperatures within the earth. During the initial stages of growth, nitrogen atoms may substitute for carbon atoms on single sites in the diamond lattice. During later stages, these nitrogen atoms migrate in the structure and tend to cluster together in energetically favorable aggregates. Diamonds containing aggregated nitrogen — that is, pairs of nitrogen atoms, or four nitrogen atoms surrounding a vacancy in the structure — are classified as type Ia. Diamonds that contain nitrogen as isolated atoms in the structure are classified as type Ib.”
   Type II diamonds, 2 percent of all diamonds, have no “discernible” nitrogen. These are further divided into type IIa diamonds that have neither nitrogen nor boron and type IIb diamonds that have no nitrogen but do have boron. If a diamond is blue, it is automatically type IIb because it is the boron that creates the blue color. However, a diamond doesn’t have to be blue to be classified as type IIb.
   Type IIa diamonds include diamonds that were mined in the Golconda area of India. Having said that, however, it’s important to note that not all Golconda diamonds are type IIa. More on that later.

   “Today, with infrared spectroscopy, specifically Fourier transform infrared spectroscopy (FTIR), diamond type can be established rapidly and conclusively,” according to the GIA. “Modern infrared spectrophotometers are able to detect trace amounts of nitrogen down to a few parts per million.” King adds that “Diamond type is very important to scientists because it so effectively categorizes the possible colors, the possible treatments, the observed fluorescence and the possible defects detected with spectroscopy.”

Type’s Impact on Price
   For the trade, those elusive “few parts per million” of nitrogen present in a diamond translate into a considerable number of dollars. Type IIa has become another form of branding and type designations are another way to set stones apart — and above others. In this case, differences in type come at a steep price. Type IIa stones command a 5 percent to 15 percent premium, when they can be found. Since type II diamonds comprise only 2 percent of all diamonds mined, they are so scarce as to barely register on the market supply.
   At the moment, the market values IIa stones higher than any others, even their equally beautiful cousins, the type Ia diamonds that artfully conceal their tiniest trace of nitrogen. A few atoms of nitrogen — too small to be visible to the naked eye and discernible only under infrared spectroscopy — determine whether a stone is labeled type I or type II. That designation on a diamond certificate makes all the difference.
   Even an observer as highly skilled as Hoda Esphahani, chief executive officer (CEO) of Safdico USA, says, “I cannot see the difference between a type Ia or type IIa.” Yet the difference has a considerable market — and price — impact.
   Barry Berg of William Goldberg says that at one point, triple EX cutting was the way people differentiated quality at the high end of the diamond market. Now, Berg says, “The difference, I feel, is more and more people want IIa; it’s another form of branding. When triple EX went from 20 percent of the market to 80 percent, it lost its cachet.” The fact is that IIa has become the new standard. Looking to stand out, sellers now are using type as a way to set their goods apart.
   For Esphahani, however, it should still be about cutting, not diamond type. “People who insist on type IIa are just taking a reading from a spectrometer to see if there is any nitrogen. None of us have the spectrometer to see that.” Only the major labs, such as GIA, have that capability. To Esphahani, “A fine type Ia diamond can be just as beautiful as a type IIa.”

Assessing Diamonds
   Henri Barguirdjian, president of Graff USA, says he uses several characteristics when assessing a diamond, not only whether it is type IIa or Ia. “We try to summarize two or three elements — color, clarity, type, fluorescence. A really fine diamond is a work of art,” he adds, not just one quality on a piece of paper. He points to the auction houses as the “detonator” that exploded the current emphasis on type IIa diamonds, and notes the popularity of type as a price determinant of diamonds has only occurred within the past five to seven years. That’s how long it has been since GIA began to add type designations to its certificates which, in turn, led to the inclusion of type information in auction house catalog descriptions.
   Just as there are Picassos worth $100,000 and others worth millions, the worth of a diamond cannot, or should not, be determined by a piece of paper. “So many people make that tragic error,” Barguirdjian notes.

Golconda or Not?
   The misuse or overuse of the term type IIa is multiplied when it comes to the way the designation “Golconda” is sprinkled around like confetti. If ever there was a name that needed trademark protection, it’s Golconda. It is important to note that the terms “Golconda” and “type IIa” are not interchangeable. Golconda, the region in India that was the only source for diamonds for hundreds of years, and where diamonds were first discovered around the fourth century B.C. and where they were mined until about 1750 A.D., did produce some of the most beautiful white diamonds ever known. They have been described as limpid, whiter than white, ice white and other admiring, if nonspecific, terms. But not all diamonds from Golconda were type IIa, even during the heyday of its production.
   According to Tom Moses, GIA senior vice president of laboratory and research, “Most of the diamonds that we have been told about or know about that came from this region are not type IIa.” In any event, no new diamonds have come from Golconda for centuries. Unless a specific diamond was mined hundreds of years ago, when the Golconda region’s mines were being worked, the use of Golconda to describe the stone is misleading.
   David Bennett, chairman of Sotheby’s jewelry department for Europe and the Middle East, says, “Before GIA and certificates became de rigueur, you talked about ‘first water’ or ‘limpidity’ and everybody knew what you were talking about. Many diamond-producing regions produce type IIa stones, including Brazil, South Africa and Central Africa. If you are going to have a white diamond, type IIa is the cherry on the cake. It’s something you can say about it, another detail, something positive.
   “There is no reliable diagnostic test that can show categorically that a diamond is of a certain geographic origin,” Bennett continues. “What we do know is that the prime origin of diamonds from antiquity was Golconda and this remained true until the discoveries of diamonds in Brazil in the 1720s.” Only documentary proof, he adds, would allow a stone to claim to be from Golconda. “The Beau Sancy is the only stone sold in recent years, at least that we know of, that fits this bill.”
   Some think the overuse of the term Golconda to refer to any fine type IIa diamond began at the GIA’s own doorstep. When questioned by Rapaport Magazine, Moses said, “We have always been careful to state that there is no scientific means to determine the geographical origin of diamonds, so I am not overly concerned what may be inferred from a GIA letter” addressing a diamond’s type.
   Still, GIA, along with other labs, issues letters that in indicating type for a specific stone, give credibility to its importance. Christie’s May 2013 Hong Kong sale, for example, offered a pearl and diamond pendant that was accompanied by two laboratory certificates, one from the GIA and the other from Gübelin, the renowned Swiss lab, both referring to the properties of type IIa diamonds. The GIA letter states, “Type IIa diamonds were first identified as originating from India, particularly from the Golconda region, but have since been recovered in all major diamond-producing regions of the world.” The Gübelin “appendix” states that “diamond of this type exhibiting an antique cutting style as well as a fine quality are very rare and will most certainly evoke references to the historic term of ‘Golconda.’” Those catalog comments are a virtual invitation to blur the line between type IIa and historic Golconda designations.

Rare but Everywhere
   Certainly the auction houses have taken advantage of the popular perception that type IIa diamonds are superior and have run with it — all the way to the bank. Although GIA has been able to discern what type — Ia, Ib, IIa, IIb — a diamond is for decades, the issuing of diamond type letters only began around 2005 or 2006, according to King. The auction houses picked up on that information immediately. Rahul Kadakia, head of jewelry for Christie’s Americas and Switzerland, notes that the type IIa nomenclature first appeared in Christie’s catalogs about six to eight years ago. Before that time, even the most glorious examples of type IIa diamonds were sold without any indication of type.
   How is it possible, then, for there suddenly to be so many type IIa diamonds turning up at the important jewelry auctions? The answer may lie in the nature of very large diamonds. For a large diamond to survive the enormous pressures of the earth, it must be chemically pure. It stands to reason that the larger the diamond, the purer the material. Or, looking at it another way, when one pages through auction catalogs of the past five to seven years, there are thousands of white diamonds that don’t carry any designation of type at all. By not stating a diamond’s type, the diamond is left to float out there, orphan-like, without a family name.
   At the end of the day, money talks and when it comes to type IIa diamonds, the amount of money can be considerable. It’s not just the 5 percent to 15 percent premium a fine type IIa can command anywhere. It’s also their rarity. “It’s not easy to find them,” Berg says. “If I went out and was willing to pay the price, they’re out there.” But, he adds, “You can find a client that will take Ia.”
   Woody Abram of Siba Corp. says customers looking for larger stones, 12 carats and above, are looking for IIa. “They’re buying certs, not diamonds,” he suggests. He estimates there is a premium of 10 percent on type IIa stones and says, “It’s a selling point.” Abram feels the market for IIa is not being influenced by the auction catalogs but rather by retail jewelers who want the IIa on a cert. John Kabbana of Global Diamond Group says the trade refers to these very white stones as the “Super Ds.”
   Rare, pure, beautiful by any description, type IIa diamonds have captured the headlines, for the moment. In a market that often needs a little something extra to close the deal, a turn of phrase or a new label is sometimes all that’s required. 

Article from the Rapaport Magazine - March 2014. To subscribe click here.

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