stone

unit of weight

Also known as: st

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Related Topics:: weight; British Imperial System; unit

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stone, British unit of weight for dry products generally equivalent to 14 pounds avoirdupois (6.35 kg), though it varied from 4 to 32 pounds (1.814 to 14.515 kg) for various items over time. Originally any good-sized rock chosen as a local standard, the stone came to be widely used as a unit of weight in trade, its value fluctuating with the commodity and region. In the 14th century England’s exportation of raw wool to Florence necessitated a fixed standard. In 1389 a royal statute fixed the stone of wool at 14 pounds and the sack of wool at 26 stones. Trade stones of variant weights persist, such as the glass stone of 5 pounds. The stone is still commonly used in Britain to designate the weights of people and large animals.

The Editors of Encyclopaedia Britannica This article was most recently revised and updated by Erik Gregersen.