Have you ever wondered why large cape yellow round brilliant diamonds seem to have all but disappeared? In this article, we’ll reveal why that is and what it means by explaining the cutting of cutting fancy color Diamonds.
A long time ago cutters learned that re-cutting warm colored (albeit not dark enough to be categorized as fancy colors) round brilliant diamonds to specially applied faceting and proportions would enhance the face-up color of the diamond. Doing so allows them to be identified as fancy colored diamonds by gemological laboratories.
Fancy colored diamonds are usually color graded by gemological laboratories based on their face-up appearance. This grading differs from their colorless counterparts, which are graded based on their genuine body colorlessness (lack of color) in the table-down or profile position.
The less color present, the higher the grade on the D to Z color scale with D being almost *completely colorless to colorless. As the grade reaches its lowest point on the alphabet scale “Z,” the grading transforms into a “fancy colored diamond color grading system.”
*There is an actual visible range within the “D” color grade
Group of fancy color Diamonds
Fancy color diamonds rough characteristics
Fancy colored rough diamonds are unique and demand very skilled analysis to plan and cut.
There is a wide range of colored rough diamonds sourced from many geographic locations. The more valuable examples are full-shaped crystals that possess an even spread of color throughout the whole rough interior with minimum irregularities.
Such stones allow for a simpler planning strategy when designing its polished outcome. With this type of rough diamond, cutters can achieve the highest yield with fewer limitations and/or compromises.
If the rough diamond possesses lighter color tones, it will probably be planned around cuts and shapes (modified cushion brilliants and radiants) with a focus on preserving weight to which also helps enhance the face-up color appearances.
However, if the rough material possesses dark and deeper colors, the planner might consider cutting to standard colorless cuts like (non-modified) brilliants and/or step cuts such as emerald cuts, etc. These cuts will display stronger light return patterns, which usually lightens the depth-of-color. They will also command a significant premium over their cut-to-enhance counterparts. We mostly encounter these cuts on deep/dark colored diamonds.
As we mentioned, colored rough is unique and will typically not be as simple to plan and cut as the examples mentioned above. Run-of-mine rough diamonds will usually possess unusual and/or broken shapes (cleavages) combined with complicated and challenging irregularities such as *twinning crystals, color zoning, internal inclusions and graining. All of which will alter the colors of the final outcome if not planned accordingly.
The more challenging the rough, the more extensive skills and experience required from both the planner and cutter. Challenging rough diamonds can force-plan divisions (splitting) of the rough into two or more satellite diamonds. This process usually lightens the depth-of-color of the original, whole diamond. In these cases, it is important that diamonds are planned for by professionals and cut to enhance the color and overall face-up appearance of the polished diamond.
Two solid colored fancy rough Diamonds from the Argyle mine
Yellow fancy color rough diamonds
Color Concentrations and Distribution in Rough Diamonds
Exterior Color Behavior
Colored rough diamonds originate in numerous locations around the world. Each mine will produce its own unique characteristics such as shapes, surface skin, and other irregularities.
Certain mines from Brazil and Africa produce yellow and green colored rough diamonds that are optically misleading at best. Natural rough diamonds will look yellow or green based on the exterior surface and or skin of the diamond, but often when you cut those gems into polished diamonds, you end up with either very light colored hues or, in many cases, colorless or near colorless diamonds.
On the other side of the coin, there are brown-toned rough colored diamonds that will produce surprisingly pinkish polished diamonds. There are also some gray-toned rough diamonds that produce beautiful blues and vice versa.
So you can see, fancy colored diamond production is an extremely complicated niche to operate within a cutting industry that is already complex enough.
A yellow rough Diamond, the color is noticeable in the skin, while the interior of the diamond is near colorless
Internal Color Behavior
To make things even more complicated, there are way too many variables in regards to color behavior during the cutting process. Here are a few that immediately spring to mind:
Friction heat (derived from the polishing wheel) is a huge factor in fancy colored materials. Heat can alter the internal structures of diamonds, which, for example, might change a rare blue color into an irreversible and common gray. In some instances, the play of color between the rare pink/purple shades and common brown shades in the cutting process can be nerve-wracking, to say the least.
Color zoning must be taken into account; many times I have personally witnessed that one diamond crystal can result in numerous diamonds of different colors each.
Color diamond absorption spectra is the science of color and its internal behavior in gems. These are innovative scientific methods based on light path calculations. In a nutshell, the longer the light path travels inside the diamond, the more color the diamond will exhibit and vice versa. This existing science has increasingly greater adoption from diamond cutters as the availability of information online expands.
If you would like to delve deeper into this scientific world, I would highly recommend reading the works and research of Sergei Sivovolenko and his team. Further info can be found on the OctoNus website.
Here is a classic example of color-zoning in Diamond material. In the center of the diamond, the left side displays much more color than the right side, it wasn’t so obvious in the face-up appearance.
Fancy Color Rough Diamond Values
If cutting fancy colored diamonds is not convoluted enough, trying to put a value on colored rough diamonds is equally challenging. This is why professionals become more dependent on the geological and rarity aspect of natural colored diamonds.
Everybody knows red is the rarest and most valuable color for natural diamonds. Is it the most beautiful colored diamond? I guess this depends on who you ask. But there is no doubt that the rarity of red provides a far greater impact on the value than the aesthetic impressions of the color itself.
Beauty is in the eye of the beholder they say. Well when speaking of colored diamonds, the paper (accompanying grading report) has a heavy burden on value. Of course, beauty is an important part of the overall value equation, but if the magic colors are not printed (or partly mentioned) in the report, it becomes only secondary to its relevance.
Cutters must purchase and value a rough diamond based on a hypothesis of the potential outcome. In other words, what is the likely grade from the laboratory report?
Color zoning and intensities need to be analyzed based on both data and experience. Even though speculation still exists, present technologies allow educated cutters to utilize modern tools to gain an important edge. Speculation and optimism can sometimes help, but can also potentially cause irreversible monetary damages. In our industry presently, there is no longer room for speculative business models.
Industry’s General Perception – Concentrating Color as an Approach
At some point in the early 1990’s cutters started researching (by trial and error) innovative ways to cut-enhance generically cut yellow diamonds. Until then we would still find older diamonds cut to display sparkle and light return as a primary objective.
I really, really miss those days.
In opposition to colorless diamonds where “cut is king,” in colored diamonds naturally “color is king.” Even though we are far beyond the lopsided cuts of the trial and error nineties, most colored diamonds are presently cut to specialized techniques and proportions. Face-up color and evenness are the primary objectives.
Since there are no standards or ideal cut proportions for colored diamonds, the range of cuts available is a real jungle of myriad cuts. Some are beautifully crafted. Others not so much.
Colorless diamond cuts are planned in their simplest form to capture the light from the source, and reflect its play-of-light back to the viewer. Colored diamond cuts attempt to catch optical color retention zones and reflect them back to the viewer.
In such cuts, the race to intensify and/or alter the face-up color is a never-ending story. Cutters constantly attempt to tweak themselves into a rarer and higher price bracket. Now imagine this process in more colors other than just yellow, then add secondary and third colors into the mix. As you can imagine, the play-of-color options become endless.
This is where fancy colored diamond cutters get to display their skills. Minimizing the brown tone in a brownish-pink can be hugely rewarding both intellectually and monetarily.
Unfortunately, the race to the best and largest colored diamonds comes at the cost of cut quality. I have witnessed many colored, polished diamonds that still possess significant natural *rough skin to intensify color zones and/or for weight preservation purposes.
On the other hand, thankfully, there are a handful of younger cutters today who are tech-savvy. They’ve learned how to utilize the technical tools available to scientifically plan cutting options based on optical light path calculations.
In such a process, the cutter can virtually estimate and predict the outcome before the physical cutting of the diamonds themselves. Diamonds originating from such analytic planning will usually display higher levels of cut craftsmanship.
*For green diamonds, it is suggested to leave natural skin for laboratory identification purposes.
On the left side a fancy color diamond cut to standard colorless 58 facets brilliant design vs. on the right a modified brilliant “cut to enhance” face up color
The GemConcepts Approach to Cutting Fancy Color Diamond
Our specialty is designing and cutting diamonds that reflect various periods of antiquity. We adhere to the proportions of yesteryear as we truly believe they offer more visual enjoyment than the standard modern proportions.
We cut our diamonds to maximize the visual enjoyment based solely on optical properties in relation to the physical action of light. Essentially, we design our diamond cuts to display specific play-of-light appearances that were found throughout history.
In our fancy colored diamonds, our experience allows us to find the perfect balance. We want viewers to enjoy both optical phenomena – a mix of color and light sparkles, with the latter playing out as the main priority.
Another aspect our diamonds offer is three-dimensional views, which go beyond an internal play of light to an additional, external light show. This show is created from the light reflections of the upper crown facets of the diamond, which optically pop out when set in their jewels.
All of this puts us at a great disadvantage in the race to acquire natural colored rough diamonds.
When choosing the right colored rough material for our diamond cuts, we must compete in a world where cutters will eventually plan and cut darker face-up models that will be laboratory graded as such.
For us to be able to offer our diamond cuts in fancy colored options, we carefully select only material that allows us to design and cut a beautiful diamond displaying the original material color. We will not compromise on its inherent play-of-light.
The economic equation is relatively simple; whatever we aim for as far as gemological color grading for our cuts, generic “cut-to-enhance” diamonds will achieve at least one higher color grade in gemological terms. This puts us at an economic disadvantage, but we believe that it is compensated for by our designs and the exceptional play-of-light that they offer.
Two fancy vivid yellow color diamonds in the table-down position – On the right a cushion modified brilliant Diamond which displays a “cut to enhance face-up” facet design. Noticeable is the extremely steep faceting by the girdle that help with the color and weight retention, then the faceting towards the culet designed to minimize contrast while reflecting the color retention zones from the girdle area.
On the left you can see an old mine diamond cut by GemConcepts to a standard 58 facet brilliant to display both the material color and play-of-light diamonds are meant to display.
Same as the previous image but on two different pear shaped fancy vivid yellow diamonds, on the right is a modified pear brilliant cut to enhance face-up color and on the left an old mine pear cut by GemConcepts.
Cutting Fancy Color Diamonds – Summary
The fancy colored diamond market can be viewed upon from two different angles.
On the one side, the darker materials yielding fancy vivid, deep and dark colors that don’t normally require any color enhancement cutting techniques. Such cuts offer appearances that do not need to sacrifice cut quality.
With lighter materials the range from fancy light to fancy intense means that planners and cutters must apply cutting techniques to darken the face-up view of the diamond. This is in the hope of earning a higher gemological color grade. Such a process will help gain the extra values.
At GemConcepts we have a singular focus – whether working on colored or colorless materials, we plan and cut our diamonds to display their genuine body color while keeping true to our cut design priorities.
The never ending battle between material color & light return in fancy colored Diamonds, this image depicts it best. Usually contrast is minimized in order to allow an even spread of color throughout the face-up of the Diamond. For us, contrast is a major component in the creation of fire and scintillation. We do not compromise on contrast!