By Ashley Bailey
, Tuesday, July 25, 2006 12:00 AM
1650: Cardinal Mazarin designed the first cross-cut diamond, which was the beginning of the brilliant style of cutting. In the early 1700s the Portuguese diamond cutter Peruzzi refined the first 58 facet brilliant cut. This style slowly evolved throughout the 1800s, known first as the old-mine cut and later as the old-European cut. These cuts still followed the contours of the rough diamond in order to retain as much weight as possible.
1860: Henry Morse opens a diamond cutting firm in Boston. By 1880 he is recutting traditional old-European cut diamonds without regard for weight loss to produce the most beautiful round brilliant of his time.
1919: Marcel Tolkowsky’s brilliant cut emerges along with his published thesis. This work becomes the standard by which future cuts of the round brilliant, including the American Ideal Cut are fashioned.
1930: Lazare Kaplan (First cousin to M. Tolkowsky) begins cutting diamonds to Tolkowsky ideal proportions.
1931-34: Robert Shipley, the educator who popularized gemology in America, founds the GIA and the AGS.
1939: GIA launch the Gem Trade Laboratories (GTL) issuing diamond certificates for color, clarity & carat weight which are still used today (pending the 2005 GIA grading system).
1946: Robert Shipley makes the distinction between brilliance and scintillation in the GIA course material.
1953: Richard T. Liddicoat develops and refines a complete grading system for diamonds that include a system for evaluating cut.
1955: The AGS Diamond Standards Committee is established. Originally a colorimetry committee, the members develop a 0-10 scale for grading diamond cut over the next decade.
1960's: AGS produces the Diamond Grading Standards manual. It undergoes many revisions over the next 30 years.
1996: AGS Laboratories open and begin grading, including cut grading for the round brilliant. Based on external proportions, the system undergoes slight revisions over the next decade. Two reports are offered: The Diamond Quality Document (DQD) which includes a grade for cut and the Diamond Quality Report (DQR) which does not.
2005: AGS Laboratories introduces an updated DQD with cut grading based on light performance. This cut grading system is also offered for the Princess Cut (the old proportions-based DQD is still offered for rounds to give the industry time to adapt to the new system).
2006: GIA laboratories introduces cut grading for the round brilliant. Based on proportions, it includes more evaluative factors than the old AGS proportions-based system.
2007: AGS Laboratories stops offering the old proportions-based DQD for rounds. Introduces cut grading for the Emerald Cut (forthcoming).
The Evolution of the Superideal Round Brilliant
In the 1970s and 80s Japanese gemologists and scientists became engaged in micro-studies of diamond cut. A scientist names Kazumi Okuda was key in the development of tools for research using colored reflectors. The Okuda Diamond Grading Microscope and the small, red-ringed “Zeiss” proportions loupe were among the first tools used to observe the precision of facet placement in diamonds. Okuda was contracted by another researcher, Tsuyoshi Shigetomi, to develop a reflector tool which eventually became a device called the Firescope in 1984. In 1985 a cutter named Kioyishi Higuchi produced the first Eightstar diamond for a Japanese businessman named Takanori Tamura using the Firescope. The Eightstar diamond was cut with emphasis on acquiring minimum light leakage and pronounced crown symmetry, or ‘arrows,' and set a new benchmark in craftsmanship as the first branded 'Superideal' diamond.
The Firescope was the first device which permitted a display of the optical performance of all 57 facets of the round brilliant. Since that time, the Gilbertson-scope (1998), Ideal-scope (2001), SymettriScope (2003), ASET (2005) and others have evolved and serve similar purposes in the analysis of light performance.
In the late 1980s Shigetomi created a copy of the Eightstar diamond he called Apollon 8, a brand that did not last. One of his associates, Kinsaku Yamashita, bought the brand and renamed the cut Hearts and Arrows. Yamashita also patented the Hearts & Arrows viewer in 1990. Somewhat different than the Firescope, this device allows the viewer to analyze the physical cut symmetry and alignment of facets in both the pavilion and crown of a diamond. It does not show optical performance; just optical symmetry and contrast effects. Shortly thereafter, the first ‘Hearts & Arrows’ diamond was produced in Japan.
In the 1990s Super Ideal cuts reached America. Since that time standards for precision patterning have continued to evolve with developing technologies and improved tools. The round brilliant diamond has been around for over 100 years but the precision patterning found in Superideal diamonds has been possible for less than 20.
In trade terms, a 'Superideal' diamond is one cut to near-Tolkowsky proportions with an extremely high level of optical symmetry. Unlike some commercial diamond which show a semblance of patterning as a result of good manufacture, true 'Superideal' diamonds are not 'happy accidents.' Those of the highest caliber are finished with true, impeccable precision as a priority, on-purpose.
What’s so Super about Superideal?
Superideals are all about maximized performance. The broad strokes include crown and pavilion angles close to Tolkowsky’s - still considered optimum for a round brilliant. This is where most “Ideal” cut diamonds stop. Super Ideal Diamonds go even deeper. Modern tooling and extra time spent eventually result in precise three-dimensional optical symmetry, where every adamantine facet is brought into optimum alignment with its opposite. This means that all of the ‘mirrors’ are precisely, kaleidoscopically brought into their most effective position.
Going even deeper, there are some Super Ideal Diamonds where seldom-discussed minor facets (lower girdles and stars) are shaped to specific proportions: The precise length and width relationships of these tiny mirrors can be harmonized for dynamic performance through the broadest range of lighting conditions.
This level of fine-tuning is a result of world-class cutters marrying old-world knowledge with new-world technology in pursuit of maximum performance in a diamond.
Marketing of Super Ideal Diamonds was driven by symbolism rather than performance when they were introduced in America. Much of that continues to this day due to origins, and the fact that the public-at-large does not have a command of diamond knowledge necessary to understand the optical benefits of patterning.
The symbolism is traceable back to Eightstar diamonds in Japan. The arrows pattern was seen as both the octagram of the I Ching and the Rinbo of Buddhism. It was said that the pattern bore a resemblance to the eight-spoked wheel of dharma, associated with spiritual perfection in the Buddhist faith. From that standpoint this pattern, and the subsequent Hearts & Arrows pattern that evolved, are products of a quest for perfection in precision and beauty in a diamond. Not everyone considers the patterns to have symbolism, but there is a great deal of importance placed on them in other cultures. Many of the diamond engagement rings sold in Japan are Hearts & Arrows.
Logically, when precision patterning reached America the emphasis on symbolism had already established itself in the minds (and cultures) of the makers. As a result, marketing efforts played up the “cute” aspect of neat little Hearts & Arrows. That approach continues in the mainstream to this day… And why not? When was the last time you walked into a traditional jewelry store and the salesman discussed Tolkowsky proportions and patterning? The public at-large does not know the difference between a diamond with a nice 40.8 PA or an undesirable 41.3, and that is a merely a surface aspect.
Therefore, mass-marketing of precision patterning still relies on the “cute H&A” moniker for the present.
Any round cut for optimum light return should have a robust balance in its light return. The benefits of patterning depend largely on lighting conditions and surroundings.
Almost any diamond will perform well in direct light, particularly the spotlighting you see in common jewelry stores. You see much brilliance (WLR) and dispersion (fire, DCLR, or chromatic/colored flashes) as well. The balance of these depends on the cut, but since so much light is entering and exiting the stone the 'fine-tuning' of what you see does not impact your eye as much as the sheer 'volume' does.
Well patterned diamonds begin to separate themselves in diffuse light. A cloudy day or an office with fluorescent lights is typically an environment in which you will see less dispersion (fire or DCLR). Well-cut diamonds return white light well, so the diamond can appear very bright, but the amount of fire you will see is often muted in this lighting condition. Scintillation is also muted in diffuse light, but a diamond with great patterning has more elements of DCLR through a normal range of tilt (AGS calls this dynamic fire) due to optimization & contrast.
Soft light, such as candlelight, lantern, computer monitor in a dark room, or many small distant light sources, is where precision patterning in a diamond really stands out. When alignment of the facets is optimized and minor facet construction is of a design that is well-balanced these diamonds maximize the return of all available light they are taking in. These are the sparklers in which you will see broad flashes from a diamond on someone's finger across a restaurant in candlelight. It’s a logical result of all of the facets, the mirrors inside the diamond, working in harmony.
Those who have made an informed decision to buy a H&A diamond will say they are worth the premium – and that they see the subtle differences outlined here.
Those who have made an informed decision not to buy a H&A diamond will say they are not worth it - and that they do not see the subtle differences outlined here.
‘Experts’ fall on both sides of the line.
It comes down to a matter of perception, personal taste and values. On a casual level any diamond that is well-cut is going to be wonderful, plain and simple. Among the millions of diamonds walking the globe you may rarely compare or care about the fractional optimization or ‘subtle insight’ of precision patterning.
I am writing from my own experiences. I began as a consumer searching for a diamond. To make a long story short, I searched malls and specialty shops and eventually had the opportunity to compare non-ideal, ideal and super ideal diamonds side by side for many hours. As a consumer the differences I have outlined above were clear to me.
Four years after my consumer journey I joined the trade. Now, as I work among hundreds of these diamonds and study minute differences in patterning & minor facet construction, the distinctions stand out even more to me.
For more specific questions ask our experts