"Sodium chloride that occurs naturally as, or obtained mechanically from, a mineral deposit and sold as large crystals. Rock salt is used to melt ice, as a food preservative, and for the production of soda ash by the glass industry. To refer to the mineral composed of sodium chloride, use \"halite.\""@en . "rock salt"@en . . "300386505" . . "2013-06-19T13:05:01"^^ . "salt, rock"@en . "2013-06-19T12:24:27"^^ . .