In salt
Although sodium is the sixth most abundant element on earth and comprises about 2.6% of the earth's crust, it is a very reactive element and is never found free in nature. Pure sodium was first isolated by Sir Humphry Davy in 1807 through the electrolysis of caustic soda (NaOH). Since sodium can ignite on contact with water, it must be stored in a moisture free environment. Sodium: geological information. Sodium is never found as the free element (native) in nature as it is so reactive. Sodium is the sixth most abundant element in the earth's crust at about 2.6 - 3.0%. The most common mineral is rock salt (sodium chloride, NaCl, or halite), but it occurs in many other minerals including sodium borate (borax), sodium carbonate (soda), sodium nitrate (Chile saltpetre). and sodium sulphate (thenardite). 0. Sodium does not exist simply as a metal in nature-it's too reactive, so it is found as a compound. Sodium is the sixth most abundant element in the earth's crust at about 2.6 - 3.0%. The most common mineral is rock salt (sodium chloride, NaCl, or halite), but it occurs in many other minerals including sodium borate (borax), sodium carbonate (soda), sodium nitrate (Chile saltpetre). and sodium sulphate (thenardite). more. answers.yahoo.com.  Answer by Liasdaughter. Confidence votes 1.6K. Sodium and potassium are two very important micronutrients of the body. They are present in every cells of the body, Sodium (Na), normally outside the cells (in the extra-cellular fluid) and Potassium (K), normally inside the cell (in the cytoplasm) .  Sodium. Sodium is most commonly found in food as salt (sodium chloride). A small amount of sodium is required by the body as it plays an essential role in keeping the fluids and electrolytes in our bodies balanced. This is important when we exercise and sodium is lost through sweating.  The most common compound of sodium is sodium chloride (common salt). It is added to food and used to de-ice roads in winter. It is also used as a feedstock for the chemical industry. Sodium carbonate (washing soda) is also a useful sodium salt. Salt (sodium chloride, NaCl) and soda (sodium carbonate, Na 2 CO 3) had been known since prehistoric times, the former used as a flavouring and preservative, and the latter for glass manufacture. Salt came from seawater, while soda came from the Natron Valley in Egypt or from the ash of certain plants. Sodium carbonate is commonly produced by the Solvay Process (also known as the ammonia-soda process), which is a complex reaction between calcium carbonate (limestone) and sodium chloride (common salt) in the presence of ammonia. Sodium carbonate, also known as soda ash, is a compound with chemical formula Na2CO3. It is most commonly found as the colourless crystalline heptahydrate, though it also occurs in other forms. Sodium Carbonate. Sodium carbonate, also known as soda ash, is a compound with chemical formula Na2CO3. It is most commonly found as the colourless crystalline heptahydrate, though it also occurs in other forms. It effloresces in air to form the monohydrate and decomposes at 34 degrees Celsius Sodium is the sixth most abundant element in the earth's crust at about 2.6 - 3.0%. The most common mineral is rock salt (sodium chloride, NaCl, or halite), but it occurs in many other minerals including sodium borate (borax), sodium carbonate (soda), sodium nitrate (Chile saltpetre). and sodium sulphate (thenardite).  Sodium is commonly found in stars. It is the most abundant alkali metal in our world's crust, taking up about ¼ of the total crust. Sodium fluoroacetate can easily be found in many plants across Brazil, Africa, and Australia. It was established as the poisonous substance of the leaves of Dichapentalum cymosum. 
http://education.jlab.org/itselemental/ele011.html http://www.webelements.com/sodium/geology.html http://www.experts123.com/q/where-is-sodium-commonly-found.html http://www.answers.com/Q/Sodium_and_potassium_are_found_mostly_in_what_part_of_the_body http://www.nutritionfoundation.org.nz/nutrition-facts/minerals/sodium http://www.rsc.org/periodic-table/element/11/sodium http://sodiumcarbonate.org/ http://sodiumcarbonate.org/ http://www.answers.com/Q/Where_is_sodium_most_commonly_found_on_earth http://creationwiki.org/Sodium
where is sodium mostly found