What’s in a carat?
“Carat” is one of the Four C’s that impact a diamond’s worth, along with cut, color, and clarity. The words “carat” and “karat” are likely derived from the same root (meaning carob pod – see karats of gold); however, in the US, the two different spellings have become indicators of stone mass (carat) and purity of gold (karat).
The word “carat” is now used to measure the weight of stones, especially diamonds. Though many people believe “carat” to be synonymous with “size,” this is not technically correct. Two diamonds could be the same carat weight, but cut in different proportions that render stones of different dimensions.
A point system provides a standard of measurement. A single carat is divided into 100 points. The weight is designated by “ct” for single stones; and by “ct tw” (carat total weight) for settings containing multiple stones. A diamond designated “.5 ct,” therefore, will be a half carat in weight. A diamond labeled “.05 ct” will be five one-hundredths of a carat or “5 points.”
“Cut” is an indicator of the proportions and balance of the facets on the stone. Shape, size, and placement of the facets all influence the determination of how well a diamond is cut. From best to worst, a diamond’s cut may be rated as Ideal; Excellent; Very Good; Good; or Fair.
“Color” signifies the extent to which a diamond is colorless, or white. The industry uses a letter scheme to measure color, from D (colorless) to Z+ (colored) diamonds. Diamonds rated D, E or F are considered colorless. Diamonds rated G-J are “near colorless,” in descending order of letter; and those rated K-Z become more yellow or darker (such as the “coffee color” or champagne diamonds) as the letters proceed to the end of the Roman alphabet. More intensely colored diamonds are also called “fancy” diamonds.
“Clarity” acts as an indicator of whether flaws are present in a diamond; and, if so, the extent to which they are visible. Here are the various designations of clarity:
- F / IF: Flawless / Internally Flawless
- VVS1/2: Very Very Slightly Included (Flaws are difficult to see even under 10x magnification.)
- VS1/2: Very Slightly Included (Flaws can be seen under magnification, but not by naked eye.)
- SI1-3: Slightly Included (Flaws visible under magnification, may be visible to the naked eye.)
- I1-3: Included (Flaws are visible to the naked eye.)
Unfortunately, there is little standardization for measurement of the various factors discussed. Determination of the 4 C’s is subjective, and different jewelers may label (and advertise!) the same stone with widely divergent designations.
At this time, we believe that GIA certification (by the Gemological Institute of America) is the strictest grading available for diamonds. GIA certified diamonds command an extra price, but with the assurance that you are getting your money’s worth.
Dan uses GIA certified diamonds whenever possible; however, smaller stones are generally not certified. Nevertheless, we purchase only from suppliers that use a strict grading scale for all diamonds and that pledge to sell conflict free stones.