Troy weight

System of units of mass

Troy weight is a system of units of mass whose origin is uncertain. By far the most common troy unit is the troy ounce (oz t), the standard mass unit for precious metals in industry and in trade; it equals 31.1034768 grams. The troy weight units are the grain, the pennyweight (24 grains), the troy ounce (20 pennyweights), and the troy pound (12 troy ounces).

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