bentonite Schlumberger Oilfield Glossary
A clay mineral that is composed principally of threelayer clays such as montmorillonite and widely used as a mud additive for viscosity and filtration control Commercial bentonite ores vary widely in amount and quality of the swelling clay sodium montmorillonite Ores of lower quality those with more calciumtype montmorillonite are treated during grinding by adding one or more of the