ranging from thousands to millions of years in shallow marine basins. It is rare to find as pure a natural zeolite as the
Bear River Zeolite deposit in Idaho.
Zeolite (Greek, zein,"to
boil" ;lithos,"a stone") is a
mineral with a porous structure that was
named by Swedish mineralogist named
Axel Fredrik Cronstedt in the 18th Century when he observed that, upon
rapidly heating the natural mineral,
the stones began to
dance as the water evaporated
There are many types of naturally
occurring zeolites that are basically
hydrated alumino-silicate
minerals with an open structure that holds a wide variety of positive
ions. These positive ions are loosely
held and can be
exchanged for others in a solution.
Zeolite is the aluminosilicate member of
the family of microporous solids known
as molecular sieves. As a molecular
sieve,
zeolite has the ability to selectively sort molecules based primarily on
a size-filtering process. This is due to
its very regular
molecular lattice pore structure. The lattices are negatively charged,
and they loosely hold positively charged cations
(an
ion
or group of ions having a positive charge)
such as calcium, sodium, potassium, and ammonium. Their ability
to exchange one cation for
another is known as their “cation exchange capacity” or CEC.