a system of weights used for precious metals and gemstones; based on a 12-ounce pound and an ounce of 480 grains
Gold and silver was measured in Troy weight but now days a metric system is used. In Troy weight : A pennyweight (dwt.) is equal to 1.5552 grams. 24 grains = 1 pennyweight = 1.5552 grams 20 pennyweight = 1 troy ounce = 31.1035 grams 12 ounces = 1 pound troy = 373.24 grams.
the unit of weight whereby 1 pound equals 14.58 troy ozs.; 1 standard ounce is .91 troy ozs.