Montmorillonite Clay the Same as Bentonite?
by Perry A~ Arledge
Bentonite and Montmorillonite clays often interchange names and
have similar properties yet vary from deposit to deposit. This
commonality can be confusing when first learning about clays.
it is not a significant difference. They are both Smectites.
Most Smectite clays have Montmorillonite properties. The
Montmorillonite name was actually given to a Smectite clay that
was found in the Montmorillon area of France. Clays are
often named after their location. Bentonite was originally
named for Smectite clay found near Fort Benton Wyoming.
Most Smectites are now referred to as Bentonites or
Montmorillonites. Like Kleenex was the only tissue for so
long that most everyone says, ‘Please hand me a Kleenex,’
instead of a tissue or by another brand name.
are very few true 100% Montmorillonite clays. Some
Montmorillonite properties are found in different percentages in
most clays. It has become a buzz word by association. It is
often found in your Bentonites but also in Illites, Kaolins and
Chlorites as well, all to different degrees.
are several references where Bentonite and Montmorillonite are
is a definition from Wikipedia:
is a very soft phyllosilicate mineral that typically forms in
microscopic crystals, forming a clay. It is named after
Montmorillon in France. Montmorillonite, a member of the
Smectite family, is a 2:1 clay, meaning that it has 2
tetrahedral sheets sandwiching a central octahedral sheet. The
particles are plate-shaped with an average diameter of
approximately 1 micrometre. It is the main constituent of the
volcanic ash weathering product, Bentonite.
and Bentonite's water content is variable and it increases
greatly in volume when the absorbs water. Chemically
Montmorillonite is hydrated sodium calcium aluminum magnesium
silicate hydroxide (Na,Ca)0.33(Al,Mg)2(Si4O10)(OH)2·nH2O.
Potassium, iron, and other cations are common substitutes; the
exact ratio of cations varies with source. It often occurs
intermixed with chlorite, muscovite, illite, cookeite and
also referred to as Montmorillonite, is one of the most
effective and powerful healing clays used to treat both internal
and external maladies.”
consists of nanometer scale of Smectite clay minerals (mainly
Montmorillonite) and micrometer scale of macro-grains (mainly
quartz). Properties of saturated Bentonite are characterized by
hydrated clay minerals.
is a dark-grey to dark-green clay-rich rock composed of mostly
Montmorillonite, with minor concentrations of cristobalite,
zeolite, and quartz, among others.”
other interlacing names are mentioned in MineralsZone.com.
and FULLER'S EARTH are the two important naturally occurring
clays of great commercial importance possessing inherent
bleaching properties. They are, therefore commonly called
bleaching clays. They fall mainly under Montmorillonite group
containing a varying amount of attapulgite.”
and Montmorillonite have similar mineral properties. The
most important of which are attributed to the Smectite Family of
clays. The Cation Exchange Capacity CEC and the Specific
Surface area of Smectites are considerable larger than other
families of clays being as they are predominately 2:1
clays. There absorption capacity is as much as 8 times
greater than other clays. (Surfacing Mining, 2nd
Edition, by B. A. Kennedy.)
clays are natural unless they have been processed or tampered
with by man. Most clays are evolved from volcanic ash that
has weathered for millions of years therefore they qualify as
natural. Pure refers to the cleanliness of the deposit.
The surface clays most likely have been exposed to pollutants
and fecal contamination. That is why you want a subsurface deep
deposit of the clay. Look for clay that has a Microbial Lab Test
clay is also a popular term and can be a Montmorillonite or a
Bentonite. Historically green clays have been known to be the
most popular healing clays and are predominately of the
Bentonite or Montmorillonite clays, though they can be from
other families as well. Green clays are generally from
marine life from lakes or inland seas or rivers that the
volcanic ash was deposited into.
to Surface Mining, 2nd Edition by B. A. Kennedy,
Bentonite is clay consisting essentially of Smectite minerals.
The term Smectite is applied as a group or family name and
Montmorillonite is a mineral species name.
in answer to the question, are Montmorillonite and Bentonite the
same? No not specifically. Are they similar in
properties and abilities? Yes. Are they used
interchangeably and synonymously? Yes.
that’s all I have to say about that subject.
Arledge is the author of Calcium Bentonite Clay Nature’s
Pathway to Healing (www.TheClayBook.com)
and numerous clay articles (www.BentoniteClayInfo.com).
She is a frequent guest on health talk radio shows. She is
dedicated to spreading the word about clay's healing potential
and putting attention on safe healing with Bentonite Clay.
She is available for lectures, radio interviews, and answering
questions on clay therapy. Perry A~ can be reached at
1-512-262-7187 and firstname.lastname@example.org.
© 2015 Perry A~