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Color & Clarity Ratings for Diamonds

All diamonds are cut differently, and the proportions of a diamond are just one of the factors that determine how much the stone sparkles or, in other words, refracts light. Two other important factors are a diamond's color and its clarity. The diamond industry has established specific techniques to classify diamonds according to these and other parameters.

Color Grading
- Diamonds are graded for color by deciding by what amount the diamond's "body color" deviates from the most colorless state. Seeing the subtle differences between one color grade and the next is difficult, so it is important to have available what the industry calls a Master Color Diamond Set with which to compare the diamond being graded. The Master Color Diamond Set consists of pre-graded diamonds in the colorless to nearly colorless range. In addition, diamonds are graded unset and in a controlled lighting environment to ensure accuracy.
Color Classification
- The diamond color grading scale classifies stones progressively from colorless to strongly colored. Colorless stones are graded D, E or F; nearly colorless stones are classified as G, H, I or J; faint yellow diamonds are graded K, L or M; very light yellow stones are designated N, O, P, Q or R; and light yellow to strong yellow diamonds are graded as S, T, U, V, W, X, Y or Z.
Clarity
- The clarity of a diamond refers to how clean or clear a diamond is internally. Most diamonds are not perfect and have blemishes, inclusions or feathers that are naturally created during the formation of the stone. The clarity scale was developed to have a universal rating system of diamond's imperfections. The ratings FI or IF are reserved for flawless stones; the classifications VVS1, VVS2, VS1, VS2 and SI1 are assigned to diamonds with increasing levels of imperfections, and those in the SI2, I1, I2 and I3 grades have the most imperfections.
Carat, Color, Clarity, Cut
- The 4 C's are traditionally thought to be the most influential factors in the pricing of diamonds, but not equally so. Though the cut of the stone can be a factor in its pricing, all well-cut stones are said to retain their value over time with any fluctuations in pricing being due mainly to changes in fashion and tastes. Color and clarity, however, are constants in the industry, regardless of other factors such as carat weight. A round cut diamond weighing 4 carats and with a color grade of D and a clarity grade of IF could retail for almost $333,000; a similarly sized stone with a color grade of M and a clarity grade of I3 could sell for approximately $17,000.

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