Evaluating Fancy Colored Diamonds

The rarer the color, the greater the role of color in determining a fancy colored diamond’s value. For example the Hancock 0.95 carat purplish red diamond has eye visible inclusions such as a deep cavity in the table top (top Center facet). Despite it’s low clarity grade and relatively small size, it holds the record price per carat for any gem ever sold at auction.

Likewise for blue green and orange diamonds, color is by far the most important value factor, so they are cut to maximize their color. On the other hand, size clarity and cut quality are more important for yellow and brown colored diamonds because there is much greater supply of them.

Shape can greatly increase the price of round fancy colored diamonds for two reasons – normally more weight is lost from the rough for rounds than for fancy shapes. In addition, if a rough diamond is cut into a round diamond, it may get a lower grade than if it’s cut as, say a radiant or princess cut. For example a Fancy Yellow round diamond may be graded as a Fancy Intense yellow diamond if it were cut as a radiant. To offset the lower color grade and loss of weight, a high premium must usually be paid for round fancy colored diamonds.

Overall, the relative importance of color for fancy diamonds does appear to be changing for some fancy colors like yellow. The percentage of fancy color diamonds receiving lab reports has also increased. This suggests that factors other than color are becoming more important in the sale of many fancy diamonds.

Before discussing fancy color evaluation we must first discuss the three fundamental color terms in GIA color terminology. They are:

Hue: GIA uses 27 hues to describe their diamond grades seven of which are the basic ones one word colores – red, orange, yellow, green, blue violet and purple. Even though gray, black and white are not considered hues and thus not listed in the GIA color chart wheel , their grading system sometimes treats them as hues. Primary fancy colored diamond hues tend to be rarer and more highly valued than transitional hues with secondary colors. Although there are exceptions like the purplish-red colored diamond.
Tone: The amount or lightness of color. Diamond tone is described with terms such as colorless, near colorless, faint, very light, fancy, and fancy. These are different form the GIA grading for transparent colored diamonds. In general the lighter the tones, the lower in value, with the exception of dark and very dark tones, which are less valuable for the different reason that their color is not as intense and rich as hues with medium tones. Blue diamonds can have darker hues than other colors and still maintain their desirability.
Saturation: The strength , purity, or intensity of the hue. When the diamond color saturation decreases, cool hues like green, blue, and violet become grayish, and warm with hues like red , orange and yellow become brownish. Colors with medium tones can have higher saturation levels then those with light and dark tones.

Taking into account the three important factors to grading fancy colored diamonds we can not start to get into the Evaluation part of the discussion. We should keep in mind the following when evaluating colored diamonds:

Unlike transitional diamonds, fancy colored diamonds are graded in the face up position, instead of primarily face down. Face up does not mean exactly straight up in one position. GIA graders rock the diamond slightly in the tray in search of the est angle to see the stone’s characteristic color – the overall color seen in the stone face-up. A diamond’s shape, faceting style and cut quality can influence its apparent face-up color. The trade and labs have agree that the face up color seen when fancy colored diamonds are worn is more important than the impression of their overall color face-down.
The highest value for fancy colored diamonds is based on the presence of color, whereas the highest value for diamonds on the D-Z scale are based on the absence of color in the diamond.
A consistent environment is important for comparing color.
The GIA saturation terms of fancy, intese and vivid have different meanings depending on the color. For example a GIA Fancy yellow diamond has a higher saturation than a fancy blue diamond or pink diamond. A fancy red diamond has a higher saturation than a fancy purple diamond.
The range of saturations possible varies depending on the hue. For example, yellow diamonds occur in a much wider range of saturations than blue diamonds, so the GIA boundaries for fancy grades in the yellow hue range allow for greater depths of fancy color than in the blue hue range.
There are noticeable differences of color with in each GIA colored diamond grade. For example, one fancy pink diamond con look distinctly lighter than another one also graded as pink fancy diamond. Therefore it is extremely important to examine fancy diamonds before you buy them.
Diamonds with an even distribution of color are more highly valued than those with an uneven color distribution. Examine the diamond from the side and face down to determine if the color is layered or concentrated in one area. A small area of color in the culet can make the entire diamond appear a fancy colored diamond when viewed face up.
Gem Laboratories can vary the way they grade and define diamond color. Even though some non-GIA labs use the GIA fancy color diamonds grading system, some don’t. Some of these labs, however may give GIA equivalent grade. This is another reason why it’s difficult to visualize the appearance of a fancy colored diamond just by reading the lab report.
The ring ring setting or mounting can have a noticeable impact on the apparent color of a diamond. For example, rose gold may emphasize the color of a pink diamond. on the other hand, the contrast of a fancy yellow diamond set against platinum or palladium may make the yellow diamond appear stronger.