BENTONITE is an
important naturally occurring clay of great commercial importance
possessing inherent bleaching properties. It is regarded to have
been formed by the alteration of volcanic ash deposits, mostly in
upper Cretaceous formations and is known as "Bleaching Clay" also
due to its high swelling property. The difference in bentonite and
other clays lies in lattice structure. The sheet of atoms in
bentonite are much thinner and more easily separable in water. That
is why bentonite occupies more surface area than other clays. This
property is known as dispersibility, which is unique to swelling
type of bentonite