Colour is an essential part of any evaluation of diamonds, and particularly diamonds. In the case of diamonds, colour is exactly what we would expect — the visible hue of a diamond. But colour gradations can be very slight and subtle, and it takes a trained gemologist with magnifying equipment, existing master stones for comparison, and a controlled lighting environment to accurately grade the colour of a given diamond. These master stones are graded and recorded at the GIA diamond lab, using white light and proper procedures. These stones are then used as a reference point for comparison in the evaluation of the colour of your diamonds.

The Diamond Colour Scale

When buying diamonds or selling diamonds, you should obtain a color grade as part of a diamond’s official certification. Colour depends upon a diamond’s chemical composition and the structure
of its crystal lattice. Diamonds are graded on an alphabetic scale ranging from D (Colorless, or “White” diamonds) to Z (very yellow or brown).

“D” diamonds are generally more desirable than diamonds closer to “O-P,” due to the relative rarity of “D” diamonds in nature. The colour of a diamond also impacts the selection of accompanying jewellery; whiter diamonds look great with white gold or platinum, while yellower diamonds look a little better with yellow gold.

The following table shows the color grades from colorless to brown:

D – E : blue-white colourless
F – G : Colourless
H – : First white colour
I – J : Very slightly coloured brown or yellow
K – L : Slightly coloured brown or yellow
O – P – Q : Yellowy or slightly brown – champagne

Diamond Types and Rare Diamonds

Diamonds are divided into Type I and Type II (with various subcategories), based upon the presence or absence of nitrogen impurities. The type of diamond accounts for certain labels for diamonds which you may have heard of, such as the Cape Series and canary diamonds.

Diamonds falling outside of the “normal” colour range—those diamonds which exhibit more intense colors—are called fancy colour diamonds. These diamonds are quite rare, and in the evaluation of diamonds they are graded on a separate colour system.

Ja-Diam’s personnel of friendly experts has a wealth of experience with respect to colour-grading a wide variety of diamonds, and even fancy colored diamonds. Contact our office for a free evaluation of diamonds today.