revolutionary France to Gandhi’s 1930 salt
march to Dandi.
Salt Production
People have been gathering crystalline salt
since prehistoric times, both from the
seacoasts and from inland salt deposits. The
rock-salt deposits, some of which are
hundreds of millions of years old, are masses
of sodium chloride that crystallized when
ancient seas were isolated by rising land
masses and evaporated, and their beds then
covered over by later geological processes.
Until the 19th century, salt was produced
mainly for the preservation and flavoring of
foods. Nowadays large amounts are used in
industrial manufacturing of all kinds, as well
as in the de-icing of winter roads, and salt
production itself has been industrialized. Most
rock salt is now mined by solution, or
pumping water into the deposits to dissolve