How Are White Diamonds Graded for Color?

Posted on March 14, 2016 by Mary Hood | 0 Comments

How Are White Diamonds Graded for Color? | Barbara Michelle Jacobs

What makes a white diamond more valuable than another white diamond?

Diamonds come in a variety of colors—some of them are very valuable—like pink and blue diamonds (including the infamous hope diamond!). (You can read more about both naturally-colored and lab-irradiated-colored diamonds in our article on colored diamonds or check out our piece on the currently trendy black diamonds).

But what about clear, or “white,” diamonds? As it turns out, the market for white diamonds is just as complex as the one for their colored counterparts. The value of white diamonds is based, in part, on where they fall on the Gemological Institute of America (GIA) Diamond D-Z Color-Grading Scale. Diamonds are evaluated and graded under controlled lighting and compared to “masterstones” of establish color value.

The scale begins with “Colorless” (D-F), followed by “Near Colorless” (G-J), “Faint” (K-M), “Very Light” (N-R), and “Light” (S-Z). The scale starts with “D” rather than “A, B, C…” because before the GIA established its current coding system, there were others in place that used the first three letters of the alphabet. Eliminating these letters served the purpose of avoiding confusion between grading systems.

According to the GIA, “a chemically pure and structurally perfect diamond has no hue, like a drop of pure water.” The more perfect and colorless the diamond, the higher its value. Using the Diamond D-Z Color-Grading Scale, diamonds that fall into the “Colorless” category, or are graded D, E, or F, are of highest value while those that fall in the “Light” category, or are graded anywhere from S to Z, are of the least value on the white diamond market.

The GIA explains that diamonds falling in the “Light” category are not considered fancy-colored diamonds. To be officially described as “colored” a brown or yellow diamond must contain more pigment than the “Z” masterstone on the color-grading scale. Alternatively, the stone must be a color other than brown or yellow—like pink or blue—to qualify as a fancy-colored diamond. 

Color is just one of the “C”s in the “Four C’s of Diamonds.” See our Diamonds 101 post for more information on cut, clarity, and carat.


Photo: Barbara Michelle Jacobs Jewelry

Posted in black diamonds, color, colored diamonds, diamonds, gemological institute of america, GIA, hope diamond



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