Troy weight

A Good Delivery silver bar weighing 1,000 troy ounces (83 troy pounds; 31 kg)

Troy weight is a system of units of mass that originated in 15th-century Kingdom of England^[1] and is primarily used in the precious metals industry. The troy weight units are the grain, the pennyweight (24 grains), the troy ounce (20 pennyweights), and the troy pound (12 troy ounces). The troy grain is equal to the grain unit of the avoirdupois system, but the troy ounce is heavier than the avoirdupois ounce, and the troy pound is lighter than the avoirdupois pound. One troy ounce (oz t) equals exactly 31.1034768 grams.

^ Hallock, William; Wade, Herbert Treadwell (1906). Outlines of the Evolution of Weights and Measures and the Metric System. New York and London: The Macmillan Company. p. 34. Retrieved 14 August 2012.

[HallockWade1906-1] Hallock, William; Wade, Herbert Treadwell (1906). Outlines of the Evolution of Weights and Measures and the Metric System. New York and London: The Macmillan Company. p. 34. Retrieved 14 August 2012.

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