Calcium Bentonite. Calcium Bentonite, also called Calcium Montmorillonite. They contain more Calcium them Sodium. It is the rarest of Smectites. Natural Calcium Bentonite that is a green clay, is well-known for its healing and curative powers because of its high adsorption and absorption powers. It can be used for external use.
The most common use of bentonite is in drilling fluids. The bentonite in the flush fluid lubricates and cools the cutting tools while protecting against corrosion. As the drilling fluid generates hydrostatic pressure in the borehole, it hinders fluid and gas penetration.
Bentonite clay is a clay which is an absorbent aluminum phyllosilicate consisting mostly of montmorillonite. The main uses of bentonite clays are for drilling mud, and as a binder, purifier, absorbent and groundwater barrier. Bentonite clay is a chemically inert, non-corrosive, natural clay.
The absorbent clay was given the name bentonite by Wilbur C. Knight in 1898, after the Cretaceous Benton Shale near Rock River, Wyoming. There are different types of bentonite, each named after the respective dominant element, such as potassium (K), sodium (Na), calcium (Ca), and aluminium (Al).
Sodium Bentonite absorbs and expands so much more than Calcium Bentonite, that if it is taken internally it could clump up with lack of water and cause constipation. However it is extremely useful as a sealant in industries because of its very swelling nature.