Apothecaries' system measure precious metals and stones. (The troy pound was already declared illegal for most other uses by the Weights and Measures Act of 1878.) In the US, the metric system replaced the apothecaries' system in the United States Pharmacopoeia of 1971. Apothecaries' system The apothecaries' system or apothecaries' weights and measures is a historical system of mass and volume units that were used by physicians and apothecaries for medical recipes, and also sometimes by scientists. The English version of the system is closely related to the English troy system of weights, the pound and grain being exactly the same in
Mithqal Mithqal Mithqāl () is a unit of mass equal to 4.5 grams which is mostly used for measuring precious metals, such as gold, and other commodities, like saffron. The name was also applied as an alternative term for the gold dinar, a coin that was used throughout much of the Islamic world from the 8th century onward and survived in parts of Africa until the 19th century. The name of Mozambique's currency since 1980, the "metical", is derived from "mithqāl". The word "mithqāl" (; “weight, unit of weight”) comes from the Arabic "thaqala" (), meaning “to weigh”. Other variants of