Since around 1900, experts in the field of gemology have developed methods of characterizing diamonds and other gemstones based on the characteristics most important to their value as a gem. Four characteristics, known informally as the four Cs, are now commonly used as the basic descriptors of diamonds; Carat, Clarity, Color and Cut.
There are four major gemological associations which “certify” diamonds: that is, define the four Cs of a diamond. While carat weight and cut angles are mathematically defined, the clarity and color are judged by the trained human eye and are therefore open to slight variance in interpretation.
Gemological Institute of America (GIA) |
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American Gemological Society (AGS) |
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International Gemological Laboratory (IGL) |
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European Gemological Laboratory USA (EGLUSA) |
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