Cut, Color, Clarity, and Carat Weight
Your guide to a diamond's quality and ultimately, value.
The concept of the 4Cs is used internationally to group specific characteristics of diamonds, to determine the quality of a diamond. Read on to learn more about the 4Cs:
How a diamond has been cut, polished, and to what proportions and symmetry, are of utmost importance as these factors determine the life, brilliance and dispersion of the diamond. If these cutting factors fall below standard, the appearance of the diamond will be adversely affected
(A) When a ray of light touches the surface of a diamond, part of the ray is reflected back. This is external reflection.
(B) The rest of the ray penetrates the stone and is then relected toward the center of the diamond. This is known as refraction.
(C) The ray of light is reflected to the surface, where it is observed as the colors of the spectrum. This is known as dispersion. Execution of the design, the precision of the cutting details and the quality of the polish are collectively called the finish.
Most fine diamonds vary in shade from colorless to yellow, brown, or gray. To determine the color grade, all submitted diamonds are compared to an internationally accepted master set of diamonds, the color of which ranges from D, or colorless (the most sought-after) to Z, (the least desirable). Deeply saturated colors occur in diamonds such as yellow, brown, orange, pink, blue, green, purple, red, etc. The most intense of these shades are graded as "Fancy" colors and labeled as such on the IGI Diamond Report.
In order to grade the clarity of a diamond, it is necessary to observe the size, number, position, nature, color, and relief of the various clarity characteristics. This analysis is carried out using a microscope and a 10x loupe under the experienced eyes of graduate gemologists.
Free of blemishes and inclusions when examined under 10x magnification.
Internally Flawless: IF
Free of inclusions. Only insignificant blemishes visible under 10x magnification.
Very Very Slightly Included: VVS1 - 2
Minute inclusions that are very difficult to locate under 10x magnification.
Very Slightly Included: VS1 - 2
Minute inclusions that are difficult to somewhat easy to see under 10x magnification.
Slightly Included: SI1 - 2
Noticeable inclusions that are easy to see under 10x magnification.
Included: I1, I2, I3
Inclusions that are obvious to a trained grader under 10x magnification and can be easily seen face-up with the unaided eye.
The weight of a diamond is measured in carats. A carat is 0.2 grams and there are 100 points (or 200 milligrams) per carat. With an accuracy of 1/100,000 ct., IGI scales provide a highly precise diamond weight that is stated on the Diamond Report to two decimal points.