Carat Weight Determines Diamond Costs – or Does It?

Each five-pound bag of potatoes costs the same at the grocery store. But not every one-carat diamond fetches the same price at the jewelry store. What gives? 

What is a Carat?

In the jewelry trade, we use the carat to measure a diamond’s weight. One carat equals 0.2 grams. Although a carat is a standard weight, not every diamond weighing in at one carat costs the same.

Is Bigger Better?

One might argue that bigger is usually better. If you are in search of the perfect diamond engagement ring, you might favor the larger 2-carat model versus the smaller 1-carat presentation. But is this really true? The answer is no. While you undoubtedly expect to pay more for a two-carat diamond ring, it may actually be comparable in cost to a one-carat jewel – under the right circumstances. In the trade, we refer to those as cut, color, and clarity, which further determine the cost of a diamond.

What are Cut, Color, and Clarity?

The diamond’s cut refers to its symmetry and proportions, which directly affects its brilliance. Finding out about the color is sometimes as easy as looking at the stone under natural light. A canary yellow piece is a rarity and will fetch a higher price than a white diamond of equal weight. Even a white diamond is not truly colorless. The color scale ranges from D (truly colorless) to Z (too much color to be considered white). We previously discussed clarity when talking about inclusions. In some stones, these are considered of value-added appeal. In diamonds, they reduce the value. A flawless stone will present with the FL rating while an I3 gem presents with too many inclusions.

Diamond Examples

Case in point is this 1.0ct princess cut diamond ring with additional channel-set diamonds in a platinum setting.  The focal stone weighs 1.0cts and fetches an E grade, which means it is colorless. Its clarity rates as VS1, which translates into a “very slightly included” mark, and notes that these are too small to see for the naked eye.
In contrast, this 1.05cts princess-cut diamond engagement ring with channel-set diamonds in platinum presents with a G to H color rating. This places it among the ranks of a near colorless stone. The clarity rating sits at SI1, remarking on a slightly included display. You should be able to make them out with a magnifying tool. Although slightly heavier than the first stone, the second has lower ratings than the first, and therefore should be less expensive.
At Peter Suchy Jewelers we are experts in all types of vintage, estate and antique jewelry. We hope you’ll stop by our showroom located at 1137 High Ridge Road in Stamford Connecticut.
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