Fancy Colored Diamonds

Because colored and fancy diamonds are so rare and pricey, they are becoming even more popular. These diamonds reflect the colors of the rainbow and dazzle in brilliant combinations of red, pink, blue, yellow, orange, green, and brown. Yellow is the most common colored diamond. Pink, red, blue, and green diamonds, on the other hand, are extremely rare. Colored diamonds also tend to be smaller than other diamonds. Rather than being cut to maximize clarity, they are cut to maximize color.
The appearance of color is created from the combined effect of three elements:

Hue - the predominant color.
Tone - the darkness of the color.
Saturation - the intensity of the color.

Diamonds occur in a limited variety of colors — steel gray, white, blue, yellow, orange, red, green, pink to purple, brown, and black. Colored diamonds contain interstitial impurities or structural defects that cause the coloration, whilst pure diamonds are perfectly transparent and colorless. In fact, black diamonds are really just highly included diamonds.

Diamonds are scientifically classed into two main types and several subtypes (in accordance to the nature of impurities present and how these impurities affect light absorption):

Type I diamond has nitrogen (N) atoms as the main impurity, with a usual concentration of 0.1%. If the N atoms are in pairs they do not affect the diamond's color; these are Type IaA. If the N atoms are in large even-numbered aggregates they contain a yellow to brown tint (Type IaB). Approximately 98% of gem diamonds are Type Ia, and most of these are a mixture of IaA and IaB material. An example of Type Ib is canary diamonds. Synthetic diamonds containing nitrogen are also Type Ib.

Type II diamonds have either none or very few nitrogen impurities. Type IIa diamonds are rare and can be pink, red, or brown colored due to structural abnormalities arising through plastic deformation during crystal growth. Type IIb diamonds usually impart a steely blue or grey color due to scattered boron within the crystal matrix. These diamonds are semi-conductors of electricity, unlike other diamond types.

Grading Fancy Colored Diamonds

Yellow or brown colored diamonds that have a color more intense than Z on a regular diamond scale are considered fancy colored diamonds. These diamonds are graded using separate systems that indicate the characteristics of the color other than its presence. A fancy colored diamond grading system is similar to those used for other colored gemstones like ruby, sapphire, or emerald.

Colored Diamond Grading System

The GIA uses specific grades to identify the ranges of color. The range is starts from Faint, Very Light, Light, Fancy Light, Fancy, Fancy Intense, Fancy Dark, Fancy Deep, and Fancy Vivid.

Advice: When purchasing a fancy colored diamond, the criteria is different. Rather than look at the cut proportions or clarity, one looks at the color's intensity. Choose a color appealing to your own personal preference.

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