Color Gia Diamond Grading

In this post you can learn about and download the official gia color scale work with an interactive diamond color chart to see the relationship between grades and colors and watch a useful gia diamond color grading video to see how gia evaluates diamond color.

Color gia diamond grading. Gems gemology winter 2008 vol. Gia s d to z diamond color grading system measures the degree of colorlessness by comparing a stone under controlled lighting and precise viewing conditions to masterstones of established color value. Gem diamonds in gia s d to z range usually decrease in value as the color becomes more obvious. However these distinctions make a very.

The gia diamond grading report contains scientifically determined information on diamond shape color clarity cut carat weight proportions and finish. Details history and methodology of the gia color scale. Gia provides a diamond cut quality grade for standard round brilliant diamonds that fall into the d to z color range. Gia developed the definitive diamond color scale or.

To develop their cut grading system gia performed extensive computer modeling of round brilliant diamonds over a 15 year period and conducted more than 70 000 observations on actual stones to validate the research. Just the opposite happens with fancy color diamonds. Many of these diamond color distinctions are so subtle that they are invisible to the untrained eye. The gia colored diamond origin report contains the same comprehensive diamond 4cs information as the gia colored diamond grading report as well as providing the geographic origin of the diamond.

For loose natural d to z color diamonds only weighing 0 15 carats or more that were submitted for rough analysis. The gia colored diamond identification and origin report the color only report is limited to color grade and the origin of the color natural. It also identifies any known treatments. Large vivid fancy color diamonds are extremely rare and very valuable.

Like the color scale gia s clarity grading system developed because jewelers were using terms that could be misinterpreted loupe clean or piqué today even if you buy a diamond somewhere else in the world the jeweler will most likely use terms like vvs 1 or si 2 to indicate the clarity of a diamond even if his or her. For standard round brilliant cut diamonds falling in the d to z color range the report also includes a. Official gia color scale. Secrets of the gem trade the connoisseur s guide to precious gemstones second ed.

Full 4cs assessment with a plotted clarity diagram geographic origin and gia report number laser inscription. The gia diamond origin report represents gia s latest innovation in diamond identification. The gia diamond grading report includes an assessment of a diamond s 4cs color clarity cut and carat weight along with a plotted diagram of its clarity characteristics and a graphic representation of the diamond s proportions.