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Diamond Color Grading Starts with the Letter "D": Why?
The color grading for colorless to near colorless scale is denoted in letter grades that run from "D" to "Z". Most diamonds used in jewelry are nearly colorless with faint yellow or brown tints. These diamonds fall in the normal color range. A diamond that is said to have 'fine color' has little or no visible coloration. The less color, the higher the value.
The GIA (Gemological Institute of America) instituted the "D-Z" scale back in 1953. Until that point, there were various poorly defined color grading scales that were confusing to consumers.
Color systems that were used ranged from numbers (0,1,2,3) to Roman Numerals (I, II, III). Letter grades were also used, e.g.; A, B, C, and even "AA". Descriptive terms such as "blue-white" and "gem-blue" were also used. All of these grades had shifting definitions and variances depending on the dealer being shopped.
GIA decided to make a fresh start and introduce a color-grading scale that would have absolutely no connection to any of the previous scales. Thus the GIA scale starts at the letter D.
Today, this GIA color grading scale has universal acceptance and is used by all grading laboratories and tradespeople.
Above: GIA Color Grading Scale.
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Comments
Why is the best colour diamond is D not A or B. There will be a reason that the grading system starts with D.
Please answer?
Posted by: why is the grading of diamond starts from D not from A? on January 24, 2008 4:01 AM
the paragraph above states that they started with the best color diamond as D because there were already several different diamond grading scales being used. At least one of those scales graded color on A, B and C. To avoid confusing overlap they started with D. If they had started with A then you could by a diamond that on one of the old systems was a B thinking that you had something good when infact you may have just purchased a GIA J.
I'm not an expert just interpreting what was written above.
Posted by: Anonymous on May 30, 2008 11:44 AM
Another reason is because of marketing... If you started with A then people would believe that anything less is inferior since A is as high as you can possibly go in the alphabet. In the case of diamonds this isn't true, a near colorless diamond can also be beautiful, so by starting at D it relieves that thought process among consumers.
Posted by: Nick on September 15, 2008 3:30 PM