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| Find out more about Color and Cut Grades |
| Home » Education » Find out more about Color and Cut Grades |
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Color describes the amount of color the diamond contains. This can range from colorless to yellow with slight tints of yellow, gray or brown. Colors can also range from intense yellow to brown, blue, green, pink and red. These fancy colors are rare and therefore more valuable.
Color differences are measured by the internationally-accepted Gemological Institute of America (GIA) grading scale, and the highest grade for a diamond with absolutely no color is D and letter grades are assigned alphabetically all the way to Z. The farther away from the letter D a grade is, the more traces of yellow or brown it appears to have. The less color a diamond has, the more valuable it is. Many times the color differences are so slight they can only be detected by comparing them to other diamonds. While most diamonds appear not to have any color at all, gasses and other elements present at the time they were formed result in slight traces of yellow or brown in some diamonds. The diamonds, which are graded as D, E or F, are called colorless diamonds. The ones, whish are graded as G, H, I, J colors are called near colorless diamonds. The diamonds, which are J or better color, are called high-end diamonds.
CUT
Cut is the only C that is controlled by man - all other characteristics of the diamond were determined by Mother Nature billions of years ago, and the Cut of a diamond can be the single most important characteristic that determines its value. Two diamonds of the exact same size with similar clarity and color grades may appear dramatically different to the eye, and have significantly different values
This is because the Cut unlocks the beauty that lies within each diamond, and the quality of the cut determines how well a diamond will reflect and refract light. In other words, the better the quality of the cut, the more scintillation, brilliance and fire a diamond will have
Diamond has a unique ability to manipulate light efficiently. This unique ability can be released and maximized only by cutting and polishing the diamond to an extremely high level of accuracy. This also requires that the cutters be willing to put forth a great deal of time and effort, adhere to some very strict geometric standards, and, most importantly, be willing to sacrifice carat weight for superior craftsmanship.
There is a set of mathematical proportions for diamond cutting that is accepted as "ideal." The closer a diamond is cut to these proportions, the more it will sparkle. Some diamonds are painstakingly polished to an exacting set of cutting and proportion standards that exceed even those considered ideal. These grades can be assessed not only for round brilliant diamonds, but for other fancy shapes as well.
The cut of a diamond should not be confused with its shape. Shapes are cut from the original rough diamond, and whatever the shape, a well-cut diamond is always better able to reflect light. Diamonds are cut into a number of shapes, which are mainly round, marquise, oval, pear, heart, radiant, cushion and emerald. The choice is a matter of personal preference. When a diamond is cut to the right proportions, it displays brilliance and fire. The standard 'brilliant' (round) cut demonstrates these qualities best. When a diamond is well cut, light is reflected from one facet to another and then dispersed through the top of the stone. If it is cut too deep, some light escapes through the opposite side of the pavilion. If cut too shallow, light escapes through the pavilion before it can be reflected.
The proportions displayed by the stone are very significant. Two of the key factors in the grading of cut quality are usually expressed on GIA grading reports, which are table and the depth ratios.
Proportions Criteria for a round diamond are as shown below:
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Premium Cut |
Tolkowsky Ideal Cut |
AGS Ideal Cut |
Total Depth |
58.8% - 63.8% |
58.0% - 63.8% |
60% - 62.9% |
Table Size |
58.0 - 61.0% |
53.0% - 58.0% |
53% - 57% |
Each cut style above represents, in the opinion of its respective designer, those proportions, which best balance the qualities of brilliance and dispersion ("fire") within a round diamond.
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