Salt which is very essential for our body and which we use in our day-to-day life is produced from seawater or the water of salt lakes, from salt springs, and from deposits of rock salt. The concentration of salt in seawater ranges from about 3% to 3.5%. Enclosed seas, such as the Mediterranean and the Red Sea, contain more salt in the water than open seas. The Dead Sea, which covers an area of about 340 square miles, contains about 10,000,000,000 tonnes of salt. On an average, a liter of seawater contains approximately 30 grams of salt. Most commercial salt is obtained from rock salt the method to obtain is to drill wells down to the salt beds. Pure water is pumped down through a pipe. The water dissolves the salt and it is forced through another pipe up to the surface.