Carat (mass) g or possibly up to 5 g less. Therefore, the metric equivalent of 1 "siliqua" was approximately 189 mg. The Greeks had a similar unit of the same value. Gold fineness in carats comes from carats and grains of gold in a solidus of coin. The conversion rates 1 solidus = 24 carats, 1 carat = 4 grains still stand. Woolhouse's "Measures, Weights and Moneys of all Nations" gives gold fineness in carats of 4 grains, and silver in pounds of 12 troy ounces of 20 pennyweight each. Carat (mass) The carat (ct) (not to be confused with the karat,
Gold coin example, a gold ingot identified as being .999 fine will be 999/1000 pure gold, with the other 1/1000 being impurities. Karat weight (K or kt) is a traditional fraction-based system used to denote the fineness of gold, with one karat being equal to 1/24 part of pure gold in an alloy. With the precision of modern assaying techniques, however, the fineness of gold ingots and bullion is more likely to appear as a decimal measurement. In this system, pure gold would be denoted as 1.000 fine. However, since absolutely pure gold is very soft and therefore not suitable for coinage