Of the tens of thousands of diamonds that I have viewed through the loupe over my 40-year career as a private jeweler, only a small number have stood out as truly exceptional and singularly beautiful. Even rarer has been the perfect stone.
Last spring, an associate of mine, whose family has been cutting and polishing rough diamonds for three generations, asked me to stop by his New York office to see what he described as a “special” stone. As he handed me a parcel paper, he looked at me with childlike expectation. Although I knew the paper held an extraordinary gem, I still was amazed by its contents: a blindingly brilliant 6.63-carat diamond radiating white fire, a sublime confluence of nature’s and man’s artistry, with a retail value approaching $1 million.
Perfection is an elusive quality and often is determined by individual perception or preference. But in evaluating a diamond, science, more than personal taste, defines what constitutes perfection. This particular stone’s round brilliant shape, which was cut to optimal measurements, reflected the greatest possible amount of light. The Gemological Institute of America (GIA) rated the gem as excellent in each of the three key categories: cut grade, polish, and symmetry. The GIA also described the stone’s proportions as super ideal, meaning that they met a precise set of numerical percentages relating to the angles of the facets in relationship to each other. The stone’s D-color grade verified that it was pure white, free of any traces of nitrogen, which impart a yellowish tint. But most significant was the stone’s clarity grading of Flawless (FL), a new category that exceeds the quality benchmark of the DIF (D-color, Internally Flawless) rating for stones that are internally free of imperfections. A Flawless stone, in comparison, is both internally and externally perfect. The latter state is achieved only after a painstaking process of removing tiny blemishes, nicks, natural inclusions, and any facets beyond a count of 58 (the established ideal).
The Flawless grade has become possible through a series of technological advances and the availability of scanning, mapping, and 3-D imaging software, with which experts can identify and locate the most minute inclusions and blemishes. Yet, even with state-of-the-art equipment, only a small number of elite diamond cutters have the skill—and the motivation—to eliminate such microscopic flaws.
Once you obtain a DIF-rated stone, you can launch the time-consuming and costly process of upgrading it to a D-Flawless (DFL) classification, though you must be prepared to sacrifice some of the gem’s carat weight. Achieving the grade may require you to submit the stone to the GIA numerous times, until at least three staff gemologists agree that it merits the rating. With each submission, you can expect to pay a fee based on stone size that can run hundreds of dollars per carat; the aforementioned stone was submitted at least three times before it achieved the designation. If a stone is rejected, you may repolish and resubmit it any number of times, however the few specialists who perform such high-level polishing may charge thousands of dollars each time they work on the gem. With smaller stones, the expenses incurred by numerous attempts tend to outweigh the potential profit, but with stones of more than 5 carats, the exponentially higher values are more likely to sustain the cost of improvement.
Still, there are inherent risks: Every time the stone is placed on the polishing wheel, the potential for damage, even disaster, exists. In the process of removing one tiny flaw, another flaw may be added or the heat of the wheel may affect the internal structure of the gem, and there is always a remote possibility that the stone literally can explode. Of course, a particular diamond may not attain the grading no matter how much technology and labor are devoted to it. Surface graining in a DIF stone, for example, will always prevent that stone from attaining the DFL rating.
Securing a DFL triple excellent rating for a diamond demands a steadfast commitment of time, patience, and resources. But if the stone attains that designation, you will possess something that few others in the world can claim: perfection.
Gemological Institute of America, 800.421.7250, www.gia.edu