Classification of Bentonite？

There are two basic types of bentonite, sodium type and calcium type.

• Sodium Type - This type has sodium in the crystal lattice and is sometimes referred to as Wyoming Bentonite. This type swells when wet and can increase as much as fifteen times its original volume when wet. Wyoming bentonite occurs in the Big Horn Basin, the Powder River Basin and along the western edge of the Black Hills. Because of this unique characteristic, Wyoming Bentonite is used as the standard against all other bentonite in the world is measured.
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• Calcium Type - This type has calcium in the crystal lattice and is sometimes referred to as Southern Bentonite. This type will swell only 2 times their unwetted volume. Southern Bentonite occurs in Mississippi, Arizona and other southern locations.