Troy weight is a standard system used in weighing gold, silver, platinum, and coins. It is also used to weigh jewels, except pearls and diamonds, which are weighed in carats. The name Troy may come from Troyes, a French town. In the 1300’s, Troyes had its own system of weights and measures. In the system of troy weight, the pound contains 12 ounces. The ounce equals 20 pennyweights, and the pennyweight equals 24 grains. The troy pound and the apothecaries’ pound both contain 5,760 grains. The pound avoirdupois equals 7,000 grains. The grains in all three systems are equal. The troy pound equals 0.373 kilogram.
