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Bentonite Science

The Science
Bentonite is the generic name for a group of volcanic originated clays of a general type found in the Montmorillon area of France; thus, the name montmorillonite. The type of montmorillonite formed (sodium or calcium) depended on the chemical mix of the ancient sea in which it evolved. It is only the sodium type (sodium montmorillonite) that we refer to when the physical properties of western bentonite is described. Chemically, (and simplified) bentonite is hydrated (Al2O3)4SiO2ēnH2O with a group of other ions as common substitutes such as iron, potassium, or magnesium depending on the source location. Bentonite is a member of the smectite family, which can be composed of two tetrahedral sheets sandwiching a central octahedral sheet. Itís the expansion of the disks during the initial absorption of water that creates the ball valve to prevent further water migration. NOTE: The use of bentonite waterproofing products in salt water must be discussed with TegraSeal Products prior to the generation of the specification.