Salt exists in two forms in nature i.e. in sea water and in the form of Halite a mineral rock of common salt. Common salt can be prepared by evaporation of sea water. Sea water is collected in division of land and it is allowed to evaporate under sunlight. Water is evaporated leaving behind mixtures of salt, form which common salt is separated by dissolving it in suitable reagent and then, recrystallizing salt from the solution.