What is salt?
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Excerpt:
Sodium chloride ( 1 2 3 4 ) or common salt is the chemical compound NaCl. Salt occurs naturally in many parts of the world as the mineral halite ( 1 2 3 4 5 6 7 8 ) and as mixed evaporites in salt lakes. Seawater ( 1 2 ) has lots of salt; it contains an average of 2.6% (by weight) NaCl, or 26 million metric tons per cubic kilometer (120 million short tons per cubic mile, an inexhaustible supply. Underground salt deposits are found in both bedded. sedimentary layers and domal ( 1 2 ) deposits. Some salt is one the surface, the dried-up residue of ancient seas like the famed Bonneville Salt Flats in Utah. Salt even arrives on earth from outer space. Conversely, surface salt depositions and man-made saltworks can be seen from space.