Zeolites occur naturally but are also produced industrially on a large scale. About 232 unique zeolite frameworks have been identified, and over 40 naturally occurring zeolite frameworks are known. Australian Zeolite is geologically old up to 300 millions of year.
Zeolites have a porous structure that can accommodate a wide variety of cations, such as Na (Sodium), K (Potassium), Ca (Calcium), Mg (Magnesium). These positive ions are rather loosely held and can readily be exchanged for others in a contact solution. Some of the more common mineral zeolites are analcime, chabazite, clinoptilolite, heulandite, natrolite, phillipsite, and stilbite.
Natural zeolites form where volcanic rocks and ash layers react with alkaline groundwater. Zeolites also crystallize in post-depositional environments over periods ranging from thousands to millions of years in shallow marine basins.