The Ideal Cut Diamonds – A Consumer’s Guide

Origin of the Ideal Cut

The pursuit of perfection is a human calling. The diamond—already perfection in the eyes of most—has been cut and shaped in an ever-changing variety of ways since modern cutting techniques were invented, all in an effort to maximize its full potential for brilliance.

Predecessors of the modern round brilliant, such as the European or Old Mine cut, were fairly deep stones with very small tables, large culets and short pavilion facets; there was no single standard way of cutting them and diamonds from that time therefore vary widely in appearance. However, in 1919, diamond cutter Marcel Tolkowsky published a doctoral dissertation that would change all of that. Using only his own visual assessments of different variations of diamond cuts, he presented a theory about the cutting angles which would create the most proportionate balance of brilliance and dispersion in a gem-quality diamond. Tolkowsky’s measurements for achieving this balance were exact and strict: a 34½° crown angle with a 53% table, which created a 16.2% crown height; and a 40¾° pavilion angle combined with a 43.1% pavilion depth. The improved cutting techniques and technology which were being developed at the same time finally allowed cutters to achieve these more precise and stream-lined designs.

Despite Tolkowsky’s theories, opinion regarding diamond proportions was not unanimous. Tolkowsky’s measurements were eagerly adopted and adhered to by the AGS. However, by the beginning of the 1950s, a backlash had begun and diamond cutters increasingly moved away from the ideal cut and toward diamonds with shallower crown angles—angles as low as 32½°—and larger tables of 60% and even 64% or 65%. Many went so far as to argue that the proportions of the Ideal Cut created an inherent over-abundance of dispersion, or “fire,” which distracted from the diamond’s brilliance. As proof that the Ideal Cut was not an absolute embodiment of perfection, they pointed to Eastern cultures, which actually considered larger tables more beautiful than the smaller ones which typified an Ideal Cut. Even those who embraced the Ideal Cut realized the impracticality of cutting diamonds to such a specific set of parameters and soon modified its definition by expanding the acceptable table size from Tolkowsky’s original 53% up to nearly 58%.

Against this backdrop of disagreement, The American Gem Society (AGS) opened its own lab in 1996. They sought to bring the public trust into their camp by providing independent documentation to confirm the superiority of the Ideal Cut. To accomplish this, the AGS began to grade and certify cut and proportions—something that had previously not been done by other labs. These grades were based on how closely a given diamond’s cut conformed to the standards established by the Ideal Cut. The grading scale ranged from 0 (the finest quality) to 10 (poor quality). Diamonds that fell within the Ideal Cut range were, of course, graded as 0. AGS’s influence on the Ideal Cut’s rise in popularity is evidenced by the fact that, today, the term “AGS zero” is synonymous with the Ideal Cut.

What Is An Ideal Cut?

By the time the AGS Lab opened its doors, the Ideal Cut was no longer conceived of as only the single set of proportions set forth in Tolkowsky’s original dissertation. Rather, it was regarded as a design based on the combination of a narrow range of proportions.

The range is:

These proportions are measured by a precisely-tuned instrument called a Sarin. No machine can measure a diamond’s quality of finish (this work is done by highly trained gemologists), but the AGS 0 cut grade also means that a diamond possesses Ideal symmetry and polish.

Technically, Ideal Cut is a brand name for diamonds that both fall within the Ideal range and are accompanied by an AGS certificate. However, most jewelers now use the term “ideal” to describe any diamond with an exceptionally fine make, whether the diamond is graded by AGS or not. Mondera uses the term “ideal” to describe any diamond that is graded as “Ideal” by AGS or as “Excellent” by GIA, as well as any diamond that was certified by GIA prior to January 2006 (before GIA began officially designating cut grades) which displays ideal proportions and an exceptional finish.

Is The Ideal Cut Really The Best

Recent research suggests that the answer is really just a matter of personal opinion.

Around the globe, the Gemological Institute of America (GIA)—a major supporter of public gemological and diamond education—is regarded as the leading expert on anything in the gem world. Their recent study on brilliance in diamonds relied on thousands of graded diamonds from the Institute’s collection, as well as on thousands of computer simulations which analyzed the way light travels into, out of, and within a diamond. The surprising conclusion of this study was that, while Ideal Cut diamonds do display a great deal of brilliance, they don’t necessarily always display the most brilliance. Rather than finding one single range of proportions that were the most brilliant, the study found a number of differing combinations of proportions that could all bring out high degrees of brilliance in a diamond. In fact, at the end of their report in the Fall 1998 issue of Gems & Gemology, William Boyajian, President of the GIA, concluded that: “Although it is not GIA’s role to discredit the concept of an ‘Ideal’ cut, on the basis of our research to date we cannot recommend its use in modern times.”

What does it Mean

In the end, it comes down to aesthetics. Personal preferences and aesthetic tastes vary widely from person to person, and it would be impractical to assume that only one type of diamond would be appropriate for all customers. It’s up to the buyer to decide what’s beautiful to him or to her. No woman who falls in love at first sight with a diamond engagement ring is thinking about the GIA or AGS. She is appreciating the unique beauty inherent in the diamond, and the love which is symbolized by the giving of that diamond.

An Ideal cut diamond displays a rare demonstration of the height of the cutter’s art, but a diamond with Very Good or Good cut also offers proof of a carefully and lovingly cut diamond.

And since Mondera will only sell diamonds that are graded as Good or better, you are ensured that any diamond that you choose from our Diamond Store will be a beautiful and worthwhile choice.

The Ideal Cut: To Buy Or Not To Buy?

If your heart is set on owning an Ideal Cut, remember that, while they are exceptional, they are generally also more expensive. Be prepared to spend a little more for an Ideal Cut than you will for a comparable diamond that is not graded as Ideal. Also, if you truly want an official Ideal Cut, make an effort to select a diamond that has been graded by the AGS rather than the GIA or another lab; with an AGS certificate, you can be guaranteed that all of your diamond’s qualities fall within official Ideal specifications.

If you are not already set on buying an Ideal Cut, do not be persuaded to buy an Ideal Cut simply because a jeweler tells you it is the only type of diamond that is brilliant. If you are concerned that a diamond with a larger table might somehow look ‘less beautiful’ than a diamond with a smaller table, please consider the following examples of the difference between two table sizes: in a 1 carat diamond, the difference between a 57% “ideal” table and a table of 59% (which is just outside the traditional ideal range) is a mere 0.13 millimeters—this is just slightly more than the thickness of a single human hair! And while the difference between a 57% table and a 62% table might sound dramatic, even this represents a difference of less than 0.30 millimeters. These subtleties are very hard to detect with the human eye, and to some people, such subtleties are not worth the added expense that buying an Ideal Cut entails.

In the long run, depending on your tastes, you can find many equally beautiful, and brilliant, diamonds in the Ideal Cut and non-Ideal ranges. Whatever type of diamond you ultimately decide to purchase, you can count on Mondera to sell only brilliant, high-quality diamonds. We will not sell any diamond that does not display the necessary brilliance to bring out the diamond’s natural.

Mondera Ideal Cut Diamonds Collection