When industry experts discuss a diamond’s color, they are typically referring to a diamond’s transparancy, or lack of color. Diamonds composed of 100% pure carbon without any impurities render completely colorless diamonds. However, almost all diamonds contain some degree of color impurity caused by lingering traces of nitrogen, boron, hydrogen or other elements. Most diamonds are affected solely by nitrogen traces, which create pale yellowish or brownish tints.
If you’re shopping for a diamond, be aware that the most valuable diamonds have the least amount of color, no diamond color. However, it is important to note that there is a class of diamonds known as fancy diamonds which are actual colored diamonds, including blue diamonds, pink diamonds and even yellow diamonds, if in fact you are looking for colored diamonds.
Diamonds can have different colors ranging from colorless (also called white), through yellow, blue, green, pink, orange, and to the rarest of all — red and black. The color of a diamond is determined by the chemical impurities as well as structural imperfections of the stone. Some diamond colors add to their value, often significantly. For examples, red diamonds are substantially more expensive than white ones—due to their rarity and natural beauty. The least expensive are yellowish diamonds, unless the stone is a very bright yellow, making it a more valuable ‘fancy’ stone.
Gemstone associations and institutes, such as GIA (the Gemological Institute of America), AGS (American Gem Society), EGL (European Gemological Laboratory), IGI (International Gemological Institute), AGA (American Gem Appraisers), etc., all have their own color grading standards and nomenclature.
Diamond color grading scale
The most widely used grading system was developed by the GIA. It grades diamonds from D (colorless) to M (faint yellow) all the way to Z (light yellow). Color grades beyond Z are considered to be ‘fancy’ grades and are graded separately.
Such diamonds are also typically more, not less, expensive than those with the yellowish hue due to their rarity and beauty.
For white diamonds, a good guide is:
- D color diamonds: 100% Colorless. The highest color grade a diamond can receive. D graded diamonds are extremely rare and very highly priced.
- E,F color diamonds – Exceptionally transparent: Extremely difficult to detect the traces of color in an E or F graded diamond. These diamonds are rare and highly priced.
- G,H color diamonds- Nearly Colorless: Unless these diamonds are compared next to a master stone of higher color grade, color is nearly indiscernible. When face up these diamond appear nearly colorless. These diamonds are still rare, but slightly less expensive and are considered a good value.
- I, J color diamonds: Nearly Colorless. Color in these diamonds is slightly detectable. The slight amount of color is imperceptible by the unaided eye once the diamond has been mounted. These diamonds are of superior value, and therefore compose the majority of diamonds that are used for engagement rings, earrings and pendants.
- K-M color diamonds – Faint Yellow. Noticeable color, although some diamonds in this range can still be fiery and beautiful.
- N-Z color diamonds – Very Light or Light Yellow. Noticeable color. These diamonds are not fit to be sold as gemstones, unless you specifically would like to have a diamond with an amber color.
What Diamond Color Grade Should I Choose?
Color is the most important factor in determining diamond price after carat weight. The difference in appearance between diamonds graded as colorless and near colorless is generally not detectible to the average consumer, but prices vary quite considerable between these two color groups. Take a look at some certified diamonds in person while window shopping and see if you can discern between different color grades. If you have difficulty differentiating between different color grades, which you probably will, then you may want to consider a nearly colorless diamond to save on your purchase.
Assuming that you are looking for a round brilliant diamond, you have a bit more flexibility in your color grade, because the sparkle and shine the brilliant cut gives it makes it more difficult to detect color. In this instance, anything over I color is usually more than adequate, and will appear completely colorless to the untrained eye unless held up against a diamond that is at least 3 color grades above it, such as an F or E colored diamond. By going with a lower color grade you save a significant amount that can go towards increasing carat weight for a larger diamond, or consider a diamond with a better cut, thus providing you with a more shine and sparkle.
When buying a diamond with a slightly yellow hue, tricks of the trade can help you mask some of that yellowish color. For instance, match the stone color to the setting’s metal color. Yellow metal (such as yellow gold) makes slightly yellow or brown diamonds appear more colorless, while darker yellows and browns look darker and richer. White metal makes slightly yellow or brown stones look more yellow or brown (typically in an unpleasant sort of way) but enhances the color of blue stones. So, if you go for a diamond below K-color grade (GIA grading classification), think about buying a yellow gold setting, rather than white gold or platinum.
Diamond Fluorescence and its effect on color
Many diamonds, when placed under UV light, emit a light glow in the same way that a white T-shirt does. Because there are a small amount of UV rays in regular daylight, some diamonds also exhibit fluorescence in natural light. On more recent GIA Diamond Grading Reports, the fluorescence of a diamond appears as a graded characteristic. Fluorescence can be graded as Inert, Faint, Medium, or Strong. To this day there is still no consensus among industry experts regarding the general impact of fluorescence on a diamond. This is because strong fluorescence in a diamond with a high color grade (D-H) can cause the diamond to appear milky or cloudy, while strong fluorescence in a diamond with a low color grade can make the diamond appear whiter. Most of the time, fluorescence has no impact on a diamond’s appearance under regular lighting conditions.