The stone or stone weight (abbreviation: st.) is an English and imperial unit of mass equal to 14 pounds (approximately 6.35 kg).[nb 1] The stone continues in customary use in the United Kingdom and Ireland for body weight.
England and other Germanic-speaking countries of northern Europe formerly used various standardised "stones" for trade, with their values ranging from about 5 to 40 local pounds (roughly 3 to 15 kg) depending on the location and objects weighed. With the advent of metrication, Europe's various "stones" were superseded by or adapted to the kilogram from the mid-19th century on.
- "stone", Concise Oxford Dictionary, Oxford University Press, 1964.
- United States. National Bureau of Standards (1959). Research Highlights of the National Bureau of Standards. U.S. Department of Commerce, National Bureau of Standards, 13.
- National Bureau of Standards, Appendix 8 .
- National Physical Laboratory, P. H. Bigg & al. Re-determination of the values of the imperial standard pound and of its parliamentary copies in terms of the international kilogramme during the years 1960 and 1961
- Sizes.com: pound avoirdupois.
- Weights and Measures Act of 1963.