Hydrated sodium alumina silicates, either naturally-occurring mined products or synthetic products, with ion exchange properties. Zeolites were formerly used extensively for residential and commercial water softening but have been largely replaced by synthetic organic cation resin ion exchangers of polystyrene divinylbenzene substrate. Modified zeolites such as manganese greensand and synthetic manganese zeolites are still used as catalyst/oxidizing filters for the removal of iron, hydrogen sulfide, and manganese.