<Tr> <Td_colspan="2"> Infobox references </Td> </Tr> <Tr> <Td> </Td> <Td> </Td> </Tr> <P> Magnesium sulfate is an inorganic salt with the formula MgSO (H O) where 0 ≤ x ≤ 7 . It is often encountered as the heptahydrate sulfate mineral epsomite (MgSO 7H O), commonly called Epsom salt . The overall global annual usage in the mid-1970s of the monohydrate was 2.3 million tons, of which the majority was used in agriculture . </P> <P> Epsom salt has been traditionally used as a component of bath salts . Epsom salt can also be used as a beauty product . Athletes use it to soothe sore muscles, while gardeners use it to improve crops . It has a variety of other uses: for example, Epsom salt is also effective in the removal of splinters . </P>

What is the chemical formula of epsom salt