CARAT
METRIC CARAT
The metric carat is divided into 100 points. A point (abbreviated “pt.”) is one hundredth of a carat. An easy way to remember this is to think of carats as dollars and points as pennies. They’re even written the same way: $1.34 means one dollar and 34 cents, and 1.34 cts. means one carat and 34 points.
Diamonds are weighed to at least a thousandth (0.001) of a carat and then rounded to the nearest hundredth, or point. Fractions of a carat can mean price differences of hundreds—even thousands—of dollars, depending on the
quality of the gem.
CARAT WEIGHT
Over a carat, diamond weights are usually expressed in carats and decimals. A 1.03-ct. stone, for example, would be described as “one point oh three carats,” or “one oh three.” Weights for diamonds that weigh under a carat
are usually stated in points. A diamond that weighs 0.83 ct. is said to weigh “eighty-three points,” or described as an “eighty-three pointer.” The second aspect of carat weight that surprises people is the relationship
between rarity, weight, and value. People expect a pound of sugar to cost twice as much as a half pound of sugar. But diamonds aren’t sold like sugar. Their prices depend on a number of variables—weight is just one of them. So it’s not always easy to understand, or explain, why a 1.00-ct. diamond is worth, say, $6,000, while a 2.00-ct. diamond of similar quality might be worth $15,000.
It’s really a simple concept: Large diamonds are more rare than small ones. You’ve already seen the relationship between rarity and value. The more scarce something is, the more it’s worth. So a larger stone doesn’t just cost
more. It also costs more per carat.