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,
Exchequer Standards inches. According to Secretary Adams, Adams goes on to say (paraphrased and simplified): Thus, the key to the whole measurement system of 1266 was the weight of the silver penny sterling. This penny was 1/240th of the Tower pound, which had been used at the London mint for centuries before the Norman conquest, and which continued as legal tender until 1527, when Henry VIII replaced it with the Troy pound. The Tower pound weighed 3/4 Troy ounce less than the Troy pound (15/16th of the Troy pound). Its penny, therefore weighed 22.5 Troy grains. There was also another pound used