Carats to Short Tons (ct to ton (US))

1 carat equals 2.204622622×10⁻⁷ short tons (rounded).

1 carat = 2.204622622×10⁻⁷ short tons

How to convert carats to short tons

To convert carats to short tons, multiply the number of carats by 2.204622622×10⁻⁷. The factor is rounded to 10 significant digits. To go the other way, multiply short tons by 4,535,923.7.

short tons = carats × 2.204622622×10⁻⁷

Example: 10 carats = 0.000002204622622 short tons.

About these units

Carat (ct)

Metric (SI)Current unit

Exactly 200 milligrams. The unit for weighing gemstones such as diamonds. Not to be confused with the karat, a measure of gold purity.

Jewellers once weighed stones against seeds. The word carat traces back to the Greek keration, meaning a carob seed, and reached English through Italian and Arabic. Carob seeds were used as balance weights for gems and gold, though their mass varies about as much as any seed does. Before 1907 each country had its own carat, ranging from roughly 187 to 216 milligrams. It was used for gold early on and for diamonds from the 1570s. An international carat of 205 mg was proposed in Paris in 1871, but the 200 mg metric carat won out.

The metric carat was adopted at the Fourth General Conference on Weights and Measures in 1907. France made it mandatory, the United States followed in 1913 and the United Kingdom in 1914. Today it is exactly 200 mg, so five carats make a gram, and it is divided into 100 points of 2 mg each; a diamond described as 25 points is a quarter carat. Carat is used for gemstones and pearls, and it should not be mixed up with karat, which measures the purity of gold and is a separate idea.

1 carat = 0.0002 kilograms (exactly).

Sources: Wikipedia: Carat (mass); NIST Guide to the SI, Appendix B.8 (mass conversions)

Short Ton (ton (US))

US customaryCurrent unit

2,000 pounds (907.18 kg). The ton used in the United States.

Wine casks lie behind every kind of ton. The word comes from tun, the term for the largest cask, and a tun of wine held roughly 2,000 pounds and took up about 60 cubic feet of cargo space. The short ton of 2,000 pounds keeps that round figure. It is used mainly in the United States and in some Canadian industries, while most of the world uses the tonne or, in the Commonwealth, the long ton.

The short ton is about 907 kg, roughly 10 percent less than a metric tonne, so the two should never be swapped when reading a statistic. The long and metric tons, by contrast, differ from each other by less than 2 percent. Weighing cargo on land is easy, but ships are traditionally described by displacement in long tons, so American shipping and naval documents can contain both kinds of ton at once. A freight bill may also use a measurement ton, which is a volume of 40 cubic feet. When writing for an international audience, spelling out short ton avoids confusion.

1 short ton = 907.18474 kilograms (exactly).

Sources: Wikipedia: Ton; NIST Guide to the SI, Appendix B.8 (mass conversions)

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