
Color
Grading Color Although color grading for diamonds has existed since ages, the turn of 19th century has seen more standardization in the color gradation process of diamonds. The diamond color grade standards set by the following two organizations are well revered and recognized in the industry.
1. Gemological Institute of America (GIA) - First laboratory in the world to address the aspects of color grading for diamonds. Grades color on an alphabetical scale of D to Z.
GIA's alphabet grade has a universal appeal. The scale begins with the highest rating of D for colorless, and travels down the alphabet to grade diamonds with traces of very faint yellowish or brownish hue. The AGS Color Grade indicates where a diamond's color falls on a numeric scale that runs from 0 (colorless) to 10 (light yellow or light brown) in 0.5 increments.
2. American Gemological Society (AGS) - Grades diamonds' color on a numeric scale of 0 to 10.
Diamond Fluorescence Fluorescence is defined as a diamond's tendency to emit a soft colored glow when exposed to long-wave ultraviolet light (such as the lighting frequently seen in dance clubs) or fluorescent light (such as the lighting frequently seen in a showroom). Most fluoro diamonds fluoresce a blue glow which gives a whiter appearance to the diamond similar to the bluing liquid that makes white laundry even whiter. In very rare cases though, strong fluorescence in a high color grade diamond may make the diamond appear foggy or oily. Fluorescence in lower color grade diamonds enhances the appearance of the diamond making the stone a great value-for-money purchase. Fluorescence is a complex phenomenon that is more debated than understood. Consumer attitude over fluorescence varies. While some people are prejudiced against fluorescence, many actually enjoy the effect. It is a matter of what appeals to the aesthetics. And the fact fluoro diamonds may cost less is a real bonus. |
