Education > Cut / Clarity / Color / Carat Weight / Certification / Conflict Diamonds The C's : ColorMost diamonds contain some hint of color. This is caused by the presence of nitrogen in the earth where they formed. Color grading for most diamonds is done on a scale of D to Z. A diamond with more color than a Z is a ‘fancy colored diamond’ and could come in any color you can imagine. These ‘fancy colors,’ however, are not graded on the same scale. Common Grading Standards
Some of the world’s largest labs are softer on color than other labs. Diamonds in most chain stores, malls and discount outlets have far more tint than diamonds sent to the stricter labs. This can give casual shoppers a false and negative first impression about warmer colors. AGS and GIA Standards
Two of the world’s strictest labs on color and clarity are the Gemological Institute of America (GIA) and American Gem Society (AGS). These labs employ strict and consistent standards. Diamonds with AGS and GIA reports command a higher premium and hold their value better than diamonds from softer labs. Cut Influences Color AppearanceDiamonds in the D-Z scale are graded face-down, viewed through the side of the pavilion. This is because shape and cut quality both influence how light gets in and out of the diamond; grading face-down allows for a neutral assessment of body color. The brilliant cutting style is most efficient for returning light, so a round brilliant or princess may show less apparent color face-up than a step cut like an emerald or asscher. Above-Average Cut Quality
When cut quality is above average, brilliants can “face up” with notably less color than the color grade they were assigned, which was determined face-down. Why? Because light gets in and out faster. This is the opposite of poor cutting (or cutting for colored stones) where critical angles are missed and light rays escape through the pavilion or make multiple bounces before leaving - which illuminates body tone. Ideal Cut Diamonds = Less Color Face Up
Diamonds that are cut to the highest level of performance have critical angles and precision-cutting so light gets in and out with the greatest intensity. Such ideal cut diamonds appear far more colorless than their laboratory cut grades. In fact, when selling ideal cut diamonds we must discourage conventional thinking of letter-ranges like DEF because these diamonds break those barriers. Ray-Tracing ExampleLight getting in and out of the diamond does not illuminate body color the way light trapped inside the diamond does (see diagram below).
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