The 4Cs of Diamonds
The cut of a diamond determines its brilliance – it unleashes its light. An ideal cut diamond is a round (also known as brilliant) or princess cut diamond that is cut to ideal proportions and angles.
To determine the cut grade of the standard round brilliant diamond – the shape that dominates the majority of diamond jewelry – The Gemological Institute of America (GIA) evaluates how successfully a diamond interacts with light to create desirable visual effects such as:
- Brightness: Internal and external white light reflected from a diamond
- Fire: The scattering of white light into all the colors of the rainbow
- Scintillation: The amount of sparkle a diamond produces, and the pattern of light and dark areas caused by reflections within the diamond
The GIA Diamond Cut Scale has 5 cut grades ranging from Excellent to Poor.
A diamond that has an even pattern of bright and dark areas, scores in the top category for all grade-setting determinants. The better a diamond is cut, the more sparkle it will have.
Diamonds that enter the Gemological Institute of America’s scale are valued according to their clarity and color. From white to yellow, diamonds receive a grade for the amount of color they contain. The scale ranges from D which is totally colorless to Z which is a pale yellow or brown color. Diamond buyers prefer colorless to near colorless diamonds.
Clarity describes the clearness or purity of a diamond – the absence of inclusions and blemishes
Almost all diamonds have tiny imperfections. Diamonds with few or no imperfections receive the highest clarity grades. Diamond clarity is a quality of diamonds relating to the existence and visual appearance of internal characteristics of a diamond called inclusions, and surface defects called blemishes. Inclusions may be crystals of a foreign material or another diamond crystal, or structural imperfections such as tiny cracks that can appear whitish or cloudy. The number, size, color, relative location, orientation, and visibility of inclusions can all affect the relative clarity of a diamond. A clarity grade is assigned based on the overall appearance of the stone under ten times magnification.
A grade is assigned to each diamond, with “F” representing a flawless diamond to “I” describing a diamond that has inclusions. Most diamonds can be found at various grades between “F” and “I.” Diamond buyers will sometimes choose a gem with some inclusions, as long as they are not visible to the naked eye.
This is the term with which people are most familiar, the measure of a diamond’s weight. The word “carat” comes from the “carob” seed, the original unit of measure for diamond traders. One carat is equivalent to 0.20 grams. The larger the carat, the pricier the diamond, although the other “C’s” can influence the final price significantly.