<Tr> <Td> ton shortweight </Td> <Td> </Td> <Td> 2240 lb </Td> <Td> Used in the iron industry in the 17th and 18th centuries . </Td> </Tr> <Tr> <Td> ton longweight </Td> <Td> </Td> <Td> 2400 lb </Td> <Td> Used in the iron industry in the 17th and 18th centuries . </Td> </Tr> <Ol> <Li> ^ Jump up to: In the UK "ton" (2240 lb) and "tonne" are usually pronounced the same, / tʌn / . As they only differ by 2%, ambiguity is not necessarily a problem; where accuracy is required in speech, "long ton" or exaggerated pronunciation of "tonne" emphasising the "e", / ˈtʌnɪ /, are used . </Li> <Li> ^ Jump up to: The longweight and shortweight tons were used as a means of making an allowance for wastage in an industrial process . The workman is provided with a longweight ton and is expected to return a shortweight ton of processed product . These measures were particularly used in the operation of hammering iron blooms into shape . </Li> <Li> Jump up ^ In other industries, a different longweight ton might be used . Coal miners delivered coal to the surface in longweight tons but were paid only for a shortweight ton . This was supposedly to allow for "dirt" (non-coal rocks) in the output . Mine owners, however, were free to set the value of the longweight ton at a value of their own choosing, and in at least some cases, it was set to 25 cwt (2800 lb) compared to the 20 cwt shortweight ton . This was a source of discontent amongst the miners who saw the practice as unfair in favour of the mine owners . </Li> </Ol> <Li> ^ Jump up to: In the UK "ton" (2240 lb) and "tonne" are usually pronounced the same, / tʌn / . As they only differ by 2%, ambiguity is not necessarily a problem; where accuracy is required in speech, "long ton" or exaggerated pronunciation of "tonne" emphasising the "e", / ˈtʌnɪ /, are used . </Li>

What is a short ton and a long ton