Convert pennyweight (troy) to carats

Explanation

From this page you can convert pennyweight (troy) to carats (or dwt to ct) simply, by using the application above.

In case you are wondering, to convert from pennyweight (troy) to carats you need to multiply by 7.7759. This factor is calculated using the respective definitions of the two units you can find below.

Formula

1 dwt≈7.7759 ct

pennyweight (troy)dwt

dimension	mass
symbol	dwt

The Pennyweight (dwt) is a unit of mass in the Troy weight system.

Definition of the pennyweight

One pennyweight is defined as being equal to 24 grains.

Value in terms of the SI

One pennyweight is exactly equal to 1.55517384 grams.

History

In the symbol, the d is the symbol of the old British penny. It stands for denarius, an old roman coin that was the equivalent of the penny. The other two letters are short for weight.

Troy Units of mass

grain	gr
pennyweight	dwt	24 grains
ounce	oz t	20 pennyweight
pound	lb t	12 ounces

The Troy weight system

The Troy weight system originated in 15th-century England. It is still in use today in the precious metal industry.

The Troy system being based on the grain, and the grain as a subdivision of the pound, it was redefined indirectly by the International Yard and Pound Agreement of 1959.

caratsct

dimension	mass
symbol	ct

The carat (ct) is a unit of mass used for measuring gemstones and pearls.

Definition of the carat

The carat was defined in 1907 as being equal to exactly 200 milligrams.

Fourth General Conference on Weights and Measures p. 89

Some Facts

The largest rough diamond ever found is the Cullinan Diamond, it weighed 3106.75 carats (621.35 grams).

The largest cut diamond on the other hand is the Golden Jubilee Diamond with a weight of 545.67 carats (109.134 grams).