The GIA is the absolute authority on all aspects of diamond grading.
For in-depth information, a visit to the GIA website is a must.
The subject of diamond color grading presented there is authentic and detailed, unlike the regurgitated versions cloned by almost every jewelry website.
Our approach is different, we explore the subject from the point of view of a jewelry designer.
• A freak of Nature: D-colored diamond
Diamonds completely void of any trace of color, which are graded as “D” (the top color grade on GIA’s scale) are rare, and therefore command higher prices. The fact that D-color diamonds are rare doesn’t mean that they are more beautiful than the rest.
The Elephant Man’s remains or Mussolini’s briefcase are valued artifacts because of their rarity, not aesthetics. The same could be said of the completely colorless diamonds and the high prices they command due to the infrequency with which they naturally occur.
For a mineral collector, a D-colored diamond can be a prized possession, but for the rest of us, using a colorless diamond in a piece of jewelry for daily wear is a waste of money.
GIA’s color scale defines D-E-F grades as “colorless,” G-H-I-J “near colorless,” K-L-M “faint,” N-R “very light,” with the rest being “light.”
• Can you tell the difference?
Diamond color grading is done by comparing a stone to a set of masters.
Diamond color is impossible to determine without special lighting and a master set to use as a reference. Even professional diamond graders at the GIA can be split in their opinion about a particular stone, in certain cases the color is decided by a majority of votes.
Diamond color perceived differently from different angles. Faceting and proportions all have unpredictable effect, for example flat stones tend to face up whiter than their grade would suggest.
Diamonds are graded upside down, comparing the amount of pigmentation of stone’s pavilion to that of a master stone.
The size of a diamond does not affect the color grade, since the grade reflects the color of the material itself.
When it comes to white diamonds, the word “color” actually means “a tint”.
The vast majority of diamonds have a small amount of yellow cast, while still appearing colorless to a casual observer.
Not only is a stone with a “sun tan” equally, if not more, beautiful than its albino counterpart, a light yellow tint does make diamonds look more natural.
• Fancy that!
Stones L and below should be classified as “specialty stones. They are not for everyone, but people, familiar with warmer colored diamonds, know how beautiful these stones are.
Most antique cuts could be found only in lower color grades. Museums all over the world display royal regalia and other historical pieces, where diamonds of different shades are all mixed together in the same piece of jewelry.
In the old days the color of a diamond was not something to be ashamed of. For example, when you visit Kremlin Armoury Chamber “Оружейная палата” (don’t forget to say “hi” to the bathroom attendant Mr. Snowden) you can see the Russian Imperial Crown embellished with stones of all the letters of the alphabet mixed in.
A Q color diamond is set right next to a G color one. Up until the 1900’s nobody cared too much whether a diamond had some yellow in it, although lack of yellow was helpful for identification purposes, since in the pre-CZ world diamonds had no colorless simulants, and zircons and topazes commonly used to make “fake” diamonds all have a yellowish tone.
Stones in the lowest end of the color spectrum are good candidates for being turned into “fancy” grade using a centuries-old foil-back technique, which is essentially adding a gold mirror “reflector” that will enhance a stone’s natural color. Not every stone is suitable for such “treatment”.
When they do, it’s a great find, that turns a $10,000 stone look into that of a $50,000 one.
In terms of value in an engagement ring:
Adding a minute amount of yellow, like that seen in H-J range stone has a decidedly positive effect on the stone appearance, it improves sharpness and depth perception, the latter is very important for step cuts, such as an Emerald or Asscher cut.
• Cut as the color’s modifier
Step cuts and antique cut diamonds in general, make warm stones appear more subdued, as opposed to brilliant cuts that tend to amplify the color. This is the reason why fancy colored diamonds are almost universally modified cushions, ovals, and radiants.
Unlike modern stones, antique cuts, such as European cut, cushion (old miner) cut, Asscher and French cut look fantastic in much wider range of colors.
There are cultural influences on the choice of color, for example in India people prefer warmer colors, in China D or E color stones are the most valued variety, in Vietnam people hunt for white stones with strong blue fluorescence and in Russia nobody seems to care about the color as long as the stone is ginormous.
Based on their purpose some colors are better suited for a:
Before the 80s, color-grading standards were more relaxed in comparison to today’s consistency in grading, in part due to technological advances such as a use of colorimeters.
• K is the new H - click to expand
In the nineties a lot of J-K, by the modern standards, stones were issued H-I certificates. This proves the point that human psychology plays a major role in color perception.
ALL diamonds grades D to Z clearly appear white to a casual observer because the amount of colored tint is insignificant even at the lower end of the scale. The color difference really shows only when stones are compared side by side.
Showcase “trickery” - using a light that somehow makes stones look “white” is an urban legend.
• About retail store lighting
The diamond color cannot be concealed, no matter what lighting is used, since the diamond color could be identified by comparison only
A retailer just doing his job of presenting diamonds in the best possible light (pun intended), just like any other retailer would, no matter what product he is selling.What would you expect him to do - put up a yellow incandescent light, so even a D-color stone looks like a fancy yellow?
The best light to observe diamond’s color is natural daylight or a full spectrum artificial lighting.
Aside from a color grade consideration, one must be careful to avoid stones with a distinct brown or green tint. GIA color grade assignment specifies a yellow hue for any diamond color that is not a fancy grade.
• Green or brown vs. yellow tint
Unlike yellow or grey, a brown or green tint is undesirable, a property of a diamond negatively affecting its appearance and value. The green and brown tints are undesirable and affected stones should be avoided.
The tint is impossible to detect for non-professionals, and even some pro’s struggle to see it. The green/brown hue becomes an issue for stones H or below.
Diamonds beyond Z-grade are called "fancy" and their value increases with the color strength. Diamonds occur naturally in almost every hue: red, green, pink, blue. They are the rarest and command astronomical prices.
There is an unfortunate inconsistency within the GIA color chart: the descriptions of the three lower color groups contains the term “yellow” instead of the more appropriate “yellow tint,” making an impression that stones are yellow in color. This is incorrect - the stones are white with a cast of yellow.
In order to describe a diamond color, we prefer to use terminology based on a range of color temperature scale seen on the chart below.
|GIA||Leon Mege||The World Jewellery Confederation||International Diamond Council||Historical Terms|
|grade and description||common sense||description||description||Antwerp||London|
|D||Colorless||Cold (fluorescent-light like) white||Exceptional white +||Colorless||Finest White||Jager|
|F||Full spectrum (natural) white||Rare white +||Face up colorless||Fine White|
|G||Near Colorless||Rare white||Top Wesselton|
|I||Slightly tinted white||Slightly colored||Commercial White||Top Crystal|
|J||Soft white||Tinted white||Top silver cape||Crystal|
|K||Faint Yellow||Silver cape||Top cape|
||Tinted color||Light cape||Cape|
|N||Very Light Yellow||Warm (incandescent) white||Tinted 2||Low Cape|
|O||Cape||Very light yellow|
|S||Light Yellow||Tinted 3||Dark cape|
Light fancy yellow with foil-back