Troy weight A grain is 20 mites, a mite is 24 droits, a droit is 20 perits, a perit is 24 blanks. In Scotland, the Incorporation of Goldsmiths of the City of Edinburgh used a system in multiples of sixteen. ("See Assay-Master's Accounts, 1681–1702, on loan from the Incorporation to the National Archives of Scotland".) Thus, there were 16 drops to the troy ounce, 16 ounces to the troy pound, and 16 pounds to the troy stone. The Scots had several other ways of measuring precious metals and gems, but this was the common usage for gold and silver. The Pound was
Troy weight Troy weight Troy weight is a system of units of mass customarily used for precious metals and gemstones. One troy ounce (abbreviated "t oz" or "oz t") is equal to exactly , (or about 1.0971 oz. avoirdupois, the "avoirdupois" ounce being the most common definition of an "ounce" in the US). There are only 12 troy ounces per troy pound, rather than the 16 ounces per pound found in the more common avoirdupois system. The avoirdupois pound has 7000 grains whereas the troy pound has only 5760 grains (i.e. 12 × 480 grains). Both systems use the same grain defined