Rock salt, also known as halite, is a naturally occurring mineral form of sodium chloride. It is typically found in large, solid masses and is often mined from underground deposits left behind by ancient bodies of water that have long since evaporated. Rock salt is commonly used for deicing roads during winter, as it lowers the freezing point of water and helps to melt ice. Additionally, it is used in water softening systems, in the chemical industry, and sometimes in cooking, particularly in salt grinders. Its crystalline structure can vary in color from clear to white, pink, or even blue, depending on the presence of impurities. Rock salt is an essential mineral with a wide range of practical applications.