Comparison of the imperial and US customary measurement systems metre, as 1852 metres. Traditionally, both Britain and the US used three different weight systems: troy weight for precious metals, avoirdupois weight for most other purposes and apothecaries' weight for medicines. However, apothecaries' weight has now been superseded by the metric system. One important difference is the widespread use in Britain of the stone of 14 pounds () for body weight. This unit is not used in the United States, although its influence was seen in the practice, until World War II, of selling flour by a barrel of 196 pounds (14 stone). Another difference arose when Britain abolished the
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