point

gem measurement

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Last updated

July 1, 2026

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The carat is a unit of weight used for precious gems like diamonds, rubies, and sapphires. Historically, the carat's weight varied by location, but in 1913, the metric carat was standardized to equal 0.200 grams. A point is equivalent to 0.01 carats. Gemstone weights are often expressed in carats, sometimes with fractional additions like 1/2, 1/4, or 1/16 of a carat. Gemstones can be cut in various ways, such as the step cut, which features parallel facets, or the rose cut, which has a domed top covered in triangular facets.123

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carat
200 g, and the point, equal to 0.01 carat, were adopted by the United States in 1913 and subsequently by most other countries. The weights of diamond, ruby, sapphire, emerald, topaz, aquamarine, garnet, tourmaline, zircon, spinel, and sometimes opal and pearl are expressed in carats.
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200 g, and the point, equal to 0.01 carat, were adopted by the United States in 1913 and subsequently by most other countries. The weights of diamond, ruby, sapphire, emerald, topaz, aquamarine, garnet, tourmaline, zircon, spinel, and sometimes opal and pearl are expressed in carats.
Read More