1 carat is 0.2g, so 1/2 of a carat equates to a 0.1g gemstone.
Forty points is equal to 40/100s or 4/10s of a carat -- almost half a carat.
It means that the total carat weight (t ct w) of both earrings together is 1 carat. In other words each stud will be half a carat.
half = 1/2 = 0.5 = 0.50 < 0.58 → Yes.
One U.S. nickel weighs 5 grams, so one-tenth of a nickel would equal 0.5 grams.
7/8ths of a carat is larger than a 1/2 carat
A carat is a measurement of diamond weight. From Amazon.com: "Carat is the unit of measurement used to describe the weight of diamonds. One carat is equal to 0.2 grams, or 0.007 ounces (avoirdupois). Five carats equals 1 gram, and 141.7 carats equals 1 ounce."
As far as gemstones are concerned, carat (karat) is used to measure their weight (as opposed to metals where carat refers to purity). There are 100 points (pts.) to a carat so a 1.0ct diamond is equal to 100 points; a half carat diamond is equal to 50 points and so on.
Half carat is the term used to measure the weight of the real diamond. A diamond's weight does not define or detract from the fact that the diamond is or is not a real diamond.
Generally, you would write .50 carat to represent a half-carat stone.
One carat weight of diamond weighs .20 grammes, so your diamond is about half that weight, or roughly half a carat.
A carat is a standard unit of measure that defines the weight of a diamond. One carat is equivalent to 200 milligrams. Carat sizes are also expressed as “points”, with a one carat diamond equaling 100 points, a one-half carat diamond being 50 points, a three-quarter carat diamond being 75 points, and so on.
A one-half carat diamond weighs 100 milligrams = 0.10 gram.
This indicator means that if all the diamonds in the ring were removed, their combined carat total weight, would be equal to one-half a carat.
A half carat diamond of this cut measures 5.2 mm at the girdle; a .65 carat diamond measures 5.6 mm at the girdle. A certified gemologist can give you the exact carat weight of your diamond.
Most people think carat is a size. Actually, it is not, it is a weight. Diamonds are measured in Carats. Carats are a metric weight unit with one equaling about the weight of a paper clip or .2 grams. The GIA website has a lot of information on different carat weight.
The descriptor '.45' usually documents the carat weight of a diamond: meaning 45/100ths of a carat, or nearly half a carat.
Carats in diamond weight can be divided into 100ths, meaning that a quarter carat stone could be described as a .25 carat diamond. In your case, you could describe this stone, as just over half a carat or .58 carat diamond. Less than full carat stones are also called points: a 58 point stone in your case.