Troy weight g, 12 oz t), while an avoirdupois pound is approximately 21.53% heavier at 7 000 grains (≈ 453.59 g). One troy ounce (oz t) is equal to grams. Also equal to avoirdupois ounces, exactly , or about 10% larger. The pennyweight symbol is "dwt". There are 24 grains in 1 dwt, and 20 dwt in one troy ounce. Because there were 12 troy ounces in the old troy pound, there would have been 240 pennyweights to the pound—the basis of the fact that the old British pound sterling of currency contained 240 pence. (However, prior to 1526, English pound sterling
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