How Important is Diamond Cut Quality?
With all of the modern advances in diamond cutting technology, and all of the studies on diamond proportions, light return, light performance, and sparkle factor, that have been conducted by various gemological laboratories, and published in practically every trade journal, I find it amazing that anybody in our industry could be unaware of the importance of diamond cut quality; but the other day while Brian was talking with another diamond cutter, I overheard the other guy say “but how important is diamond cut quality anyway, do you think that people can really tell the difference between a pavilion angle which is 40.8 degrees and one which is 41.2 degrees?”
I walked into the office and sat down, I knew that this was going to be an interesting discussion, and I was supposed to be joining the meeting in a few minutes anyway…
Brian smiled and leaned back in his chair, opened his arms a bit, as he extended his palms upward, and asked “would you prefer a Porsche which is turbo charged and finely tuned for optimum performance, or one which is standard?” to which the other diamond cutter said “Well, turbo charged of course!” to which I had to laugh because the principle is truly the same whether we’re talking about cars or diamonds.
The Pavilion Angle of a Diamond dictates Light Return:
The pavilion angle of a diamond is the primary reflective surface which directs the light which enters a diamond through the crown, back up towards the person viewing the diamond. If the pavilion angle is too shallow, or too steep, the light will not be directed in the right direction, and the volume of light return may decrease substantially.
When the pavilion angle is properly cut, the light return of the diamond will be exceptional, and to answer the question presented by the diamond cutter whom Brian was speaking with, there is a rather distinct difference in the brightness of a diamond which is cut with a 40.8 degree pavilion angle and one which is cut with a pavilion angle of 41.2 degrees, and I think that pretty much everybody could see the difference if they were presented with the opportunity to compare the two diamonds side-by-side.
The Crown Angle of a Diamond controls the Sparkle:
This is a bit of an over-simplification, because every facet on a diamond creates sparkle and is a contributing factor of light return, but the crown angle of a diamond is the primary indicator of the type of sparkle that will be exhibited by a diamond…
At Brian Gavin Diamonds, we like to produce round brilliant cut diamonds which are cut within a range of proportions which is the center of the range designated by the American Gem Society Laboratory (AGSL) for their zero ideal cut proportions rating. We do this because it is the “sweet spot” which is considered to be optimum for light return and a degree of brilliance and dispersion which is balanced.
We could choose to cut diamonds with crown and pavilion angles which are slightly shallower or slightly steeper, but this would result in a lower volume of light return, and diamonds which were either more brilliant, or more dispersive, rather than exhibiting a virtual balance of the two.
From our perspective, diamonds which are cut with crown and pavilion angles which are too steep, or too shallow, were cut to maximize the yield of carat weight, rather than cut to maximize beauty and visual performance. It is a choice which every diamond cutter has to make, with every diamond that is designed and produced, diamond cutters like Brian Gavin focus on producing diamonds of exceptional diamond cut quality and optical symmetry, while others cut to the outer edges of what is considered to be ideal, perhaps because they don’t believe that their customers will be able to tell the difference.
The same principal holds true with Brian’s choice to produce diamonds which exhibit a crisp and complete pattern of hearts and arrows for the Brian Gavin Signature collection.
While Brian realizes that the highest possible grade to be obtained for a round brilliant cut diamond from the AGSL is AGS Ideal-0 and that the grading platform does not take the optical symmetry of a diamond into account, he still insists that the diamonds in his Signature collection be cut to a level of optical symmetry which results in a crisp and complete pattern of hearts and arrows, like the one pictured to the left, from this 1.706 carat, G-color, VS-1 clarity, Brian Gavin Signature diamond. Hearts and Arrows patterns this precise are present within less than 0.001% of round brilliant cut diamonds, neither the AGS nor GIA gemological laboratories take these patterns into account when grading.
However Brian Gavin provides photographs of the hearts and arrows patterns which are visible within each of his Signature round diamonds on the diamond details pages, along with images of the diamond as seen through other reflector scopes, such as an ASET Scope, and an Ideal Scope, which are used to judge the optical symmetry, brightness, and degree of light leakage which is present within a diamond, so that our customers can be assured that every diamond we produce is cut to the highest standards.