Salt in the ocean comes from the land. The elements that make upsalts, such as chlorine and sodium, started out in rocks. Water andacids eroded the rocks, and rivers carried the elements into thesea. The oceans usually contain 35 parts of salts for every 1000parts of sea water. This is lower in some places where there is alot of fresh water coming into the ocean. It is higher where theSun is very strong and evaporates more of the water. When all thewater is gone, the salts are left behind as solid, whitecrystals.The right amount of salt is a very important part of our diet.In ancient times, salt was worth its weight in gold. People used itto flavor and preserve their food. Without salt, the food wouldspoil. For this reason, salt became a symbol of purity. Somesacrifices in the Old Testament included salt (Leviticus 2:13;Ezekiel 43:24). Jesus called faithful people "the salt of theearth," and the Apostle Paul said that our speech should be"seasoned with salt" (Colossians 4:6).