Color
In diamonds, rarity equals value. The value of diamonds is based on the absence of color, as colorless diamonds are the rarest. Fancy color diamonds – those outside the normal range of colors – the rarest and most valuable colors are saturated pink, blue and green. In all cases, even very small color differences can have a big impact on value.
Compared to fancy yellow and brown diamonds, diamonds with a visible hint of any other shade are considerably rarer. Even in light tones and low saturation, as long as the color shows face up, it qualifies as fancy color. Red, green, and blue diamonds with medium to dark tones and moderate saturations are extremely rare.
The classification of fancy colored diamonds is complex and specialized, therefore high-level specialists are needed to complete the evaluation process with precision.
The GIA system for grading fancy-color diamonds is designed to accommodate the fact that not all colored diamonds have the same depth of color. For example, yellow diamonds occur in a wide range of saturations, while blue diamonds do not.
Fancy-colored diamonds have a range of color intensity, with intense and bright-colored diamonds being the rarest.
Red or reddish-colored diamonds are extremely rare and highly valued. Pure pink diamonds are more popular than purple, orange, brown or gray diamonds. Professionals in the trade market have some very attractive stones in this category as “pink” and some stones with purple hues as “purple” diamonds.
Blue diamonds are extremely rare. They generally have a gray tint, so they are rarely as saturated as blue sapphires. Their color is caused by the presence of boron impurities – the more boron, the deeper the blue.
Blue diamonds are extremely rare, and strongly colored diamonds are some of the rarest gemstones.
Fancy green diamonds are usually lighter in tone and less saturated. Their color is often faded, with a gray or brown cast. The shade is generally in the yellowish-green category. In most green diamonds, the hue is limited to the surface and rarely extends throughout the stone. That’s why the cutters try to leave as much of the natural stone as possible around the girdle.
Green diamonds get their color when radiation displaces carbon atoms from their normal positions in the crystal structure. This can happen naturally when diamond deposits are near radioactive rocks or artificially as a result of irradiation treatment.
Naturally colored green diamonds are extremely rare. Due to their rarity and the possibility of artificial color treatments, green diamonds are always viewed with suspicion and carefully examined in gemological laboratories. Even so, advanced gemological testing cannot always determine the origin of color in green diamonds.
Brown is the most common diamond color and has also been used in jewelry since ancient times. The 2nd century Romans set brown diamonds in rings. However, in modern times, they took some time to become popular.
Brown diamonds were usually considered good only for industrial use until the 1980s, when abundant quantities began to appear in the production of the Argyle mines. The Australians faceted them and mounted them in jewelry. They gave them names like “cognac” and “champagne”. The marketing worked, and brown diamonds are now found in many mid-priced jewelry designs.
Diamond appraisers look for the strongest color zones in the diamond when grading them. These are represented by the darker shaded areas in the illustrations for each Fancy colored diamond.
Brown diamonds range in tone from very light to very dark. Consumers generally prefer medium to dark brown diamonds with a warm, golden to reddish appearance. They generally show a hint of greenish, yellowish, orange or reddish colors.
Yellow is the second most common color of the Fancy diamond. Yellow diamonds are sometimes marketed under the name “canaries”. Although this is not a proper grading term, it is commonly used in the trade to describe fancy yellow diamonds.
Until the late 1990s, there was not much demand for black diamonds. But designers began to use them in jewelry, especially in contrast with tiny colorless diamonds in pave settings, and they began to gain popularity.
There are also fancy white diamonds, those have a milky white color. Sometimes white diamonds are cut so as to display a bright color like opal.
There are also gray diamonds. Most of them contain a high level of hydrogen as an element of impurity, which probably causes their color.
Clarity
With fantasy color diamonds, color is the dominant value factor. Even diamonds with numerous inclusions that result in a low degree of clarity are appreciated by connoisseurs if they present an attractive color seen from above. Of course, inclusions that threaten the durability of the stone can significantly reduce the value of a diamond of fancy color. Fancy diamonds may exhibit color granulations, which is considered an inclusion.
Cut
The size and shape of the cut are two aspects that can influence the color of the diamond. The larger a diamond is or the deeper its pavilion is, the more light can circulate in it. This can often lead to a richer, more intense color.
The style of the cut can also influence the color. Cutters have found that certain styles—usually mixed cuts such as radiant—can intensify the yellow color in diamonds that are toward the lower end of the color grading scale from D to Z. When carefully modeled, as cuts radiant, many yellow stones – once called “capes” – can turn a fancy yellow when viewed face up. This perceived improvement in color increases the price per carat. As an added benefit, the radiant style offers a higher yield from the raw than a standard round cut.
Fantasy color diamonds are often cut into fancy shapes.
Carat
As with diamonds in the normal D-Z color range, large fancy color diamonds are rarer and more valuable than small ones.
The Jaune Vagabonde Ring features small white and yellow diamonds surrounding a 10.81-carat yellow diamond. – Jaune © Stray Ring 2011 Fabergé Ltd
- Article and pictures GIA.com
