Calgon is a bran registered trademark of different corporations. The original product consisted of powdered sodium hexametaphosphate (amorphous sodium polyphospate), which in water would complex with ambient calcium ion and certain other cations, preventing formation of unwanted salts and interference by those cations with the actions of soap or other detergents. Its name suggests "calcium gone". Originally promoted for general use in bathing and cleaning, it gave rise to derivative products which have diverged from the original composition.