With the diamond industry becoming as robust and lucrative as it is today, there has been an increasing need to rate and classify colored diamonds according to quality and value. Several regulatory and standards commissions have been set up to educate buyers and sellers alike in the criteria that make a good diamond.

Experts classify the value of colorless diamonds and colored diamonds by using four general criteria, commonly known as the 4 C’s. These criteria are color, cut, carat, and clarity. Each one of these categories has sub categories that are comprehensively explained and formulated, so that every diamond is rated accurately and according to its merits and flaws.

It is important to note that the 4 C's have a very different affect on colored diamonds than they do on colorless. In this article we will focus on the 4 C's, as they pertain to understanding colored diamonds.

Determining Body Color of Colored Diamonds

For rare colored diamonds, body color is one of the most important characteristics. The circumstances that collaborate to make fancy diamonds are rare and unpredictable, resulting in a cascade of colors and hues in different intensities. Body color refers to the actual shade of the diamond, and the deepness or lightness of its color.

While there are many varieties available, it is the tone, shade, and saturation of the color that determines the value. Some colors are common and only become valuable when the color is particularly intense yellows and browns, for example, while others are extremely rare and always valuable. The diamonds outside the normal color range - reds, saturated pinks, blues and greens - are the rarest and most valuable.

The Gemological Institute of America, or the GIA, is a regulatory board that rates and classifies diamonds using the four C’s. Their system of color grading fancy color diamonds accounts for the fact that not all colored diamonds have the same depth of color. The system ranks diamonds upwardly in value from fancy light to fancy to fancy intense and finally to fancy vivid, fancy dark, and fancy deep. The last three have equal value and are applied depending on the color.

The slim chance of impurities forming in high enough concentration to severely affect the shade of a colored diamond is the main reason why color and vibrancy play such an integral part in determining diamond value.

The deepness of hue or shade is a very important factor when considering the purchase of a diamond. It is a characteristic that is exclusive only to colored diamonds (for obvious reasons) and a slight alteration in shade is the difference between a million and ten times that. Note that the value of diamonds is mostly calculated by a formula accounting for its shade and carat.

The Diamond Cut of Colored Diamonds

Shape, style, and size can affect the color of fancy colored diamond. Generally, the larger the diamond, the farther light can travel through it which can lead to more intense color. It is advisable to understand the terminology between diamond shapes. When diamonds are mined, they are rough, and for them to become the sparkling gems we know and love, diamond cutters must cut the gems into smaller pieces using lasers and special blades. The diamonds are then shaped mechanically or by hand to create a flat top - the table, the rim, and the facets. The diamond is then polished to give it the final sparkle.

Carat weight

As with white diamonds, carat or weight is an important consideration for any buyer. One carat equals 200 milligrams and the more the carats, the greater the value of the diamond. For diamonds under one carat, each carat is divided into 100 points, just like cents to the euro. Therefore, 0.75 carat is 75 points.


As opposed to white diamonds, clarity is not a dominant value factor in fancy colored diamonds. As mentioned above, the core value of a fancy colored diamond is derived from its color. Clarity describes the clearness or purity of a diamond. This is determined by the number, size, nature, and location of the internal (inclusions) and external (blemishes) imperfections. However, diamonds with low clarity but excellent face-up color can still be prized. Inclusions devalue fancy colored diamonds when they affect the gem’s strength.