Salt (halite) is the only rock that is edible for humans. It is 40% sodium and 60% chlorine. It is needed by the human body to regulate fluid balance. Human cells cannot function without salt. It is literally carried in a person's blood system.

Halite is the mineral name for the substance that everyone knows as "salt". Its chemical name is sodium chloride and a rock composed primarily of halite is known as "rock salt". Halite occurs in vast beds of sedimentary evaporite minerals that result from the drying up of enclosed lakes, beaches and seas. Himalayan salt is a marketing term for halite (rock salt) from Pakistan, which has been sold by various companies in Europe, North America and Australia since the early 21st century.

With salt or edible salts, most are identified by such characteristics as their geographic origin, method of preparation, natural impurities, additives, flavorings or intended purpose (such as pickling or curing).

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