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
Silver center cent of the new nation's coinage should be approximately equal to its face value. Some merchants would refuse to accept coins that did not meet this standard. For most denominations, bullion parity was achieved by producing the coins in a gold or silver alloy. However, the Coinage Act of 1792 specified that the cent was to consist of 11 pennyweight (264 grains or 17.1 g) of pure copper. Such a weight, needed to maintain intrinsic value, would have been too heavy for practical everyday use. U.S. Secretary of State Thomas Jefferson suggested an alternative: a coin made of an alloy that