When people talk about how many carats a diamond has, they are actually referring to the diamond weight, not the diamond shape or size.

When you compare diamond carat sizes it’s important that you also consider each diamond’s cut.

A diamond with a larger carat weight may appear smaller than a smaller carat weight diamond if the diamond cut is poorly done and/or deeper.

The same applies to diamonds of equal carat weight. Diamond carat weight is how many metric carats a diamond weighs. A carat is equal to 200 milligrams. Each carat of a diamond can be subdivided into 100 different “points” in order to precisely measure it. Each point is a unit of weight.

If a diamond weighs less than one carat, the number of points it has is used to describe it. For example, a jeweler might use the phrase “twenty-five pointer” to describe a diamond with 0.25 carats.

THOMAS NEVIN JEWELER DIAMOND BUYING TIPS

Remember that carat refers to a cut diamond’s weight measurement, not its shape or size.

Cut and carat should be considered together when comparing diamonds.

A larger carat diamond that has been poorly cut (lower cut grade) will look smaller to the naked eye than a smaller diamond that has been expertly cut (higher cut grade.)

Jewelers consider some diamond weights as “magical.” These are the ½ carat, ¾ carat, and 1-carat diamonds. The naked eye cannot see any difference between a full-carat diamond and a 0.99-carat diamond, but the difference can certainly be felt in the pocketbook!

To get the most from your money it is suggested that you “buy shy” by choosing a diamond that weighs slightly below ½ or 1 carat.

For example, rather than a full-carat diamond with 100 points, you might want to select a 0.95 diamond carat weight. This will save you quite a bit of money and no one will ever notice the difference.

Remember that the prices of diamonds can increase exponentially. The larger the diamond in terms of carat weight, the more it will cost due to its rarity.

Diamonds with higher weights cost more money. That’s just a fact.

In measuring the carat weight of a diamond, two factors are taken into consideration:

1. DIAMETER ACROSS THE TOP
   A measurement, in millimeters, is taken across the diameter at the top of the diamond because this is the part that’s seen once the diamond is set into the ring.
2. CUT GRADE OF THE DIAMOND
   The diamond’s cut grade is also considered because a beautifully cut diamond will reflect the light much better at the top, which makes it look larger.

   A well-cut diamond is graded “very good” or higher. How would these two weight measures help you when making a purchase? The diameter of the diamond, along with its cut grade, clearly shows that smaller carat weight diamonds look larger when they are well cut, with a “very good” or “ideal” cut grade. On the other hand, a diamond with a larger carat weight can easily look smaller if it has a lower cut grade of “poor,” “fair,” or just “good.”
   
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