A rock composed essentially of a crystalline clay-like mineral formed by devitrification and the accompanying chemical alteration of a glassy igneous material, usually a tuff or volcanic ash.
Used as a foundry sand, paints, fuller's earth, drilling mud, bleaching clay, filtering agents, water impedance, inks, additive to ceramic materials, and iron ore pelletizing. Used in pharmaceuticals, beverage, food, cosmetics, and personal care products (Suspending agent, gellant and binder). Bentonite possesses thixotropic properties and deposits a thin water proofing film on the walls of the bore holes & thus renders permeable formations impermeable. Both natural & synthetic Bentonite are used in preparation of drilling muds. It is mainly used as circulation mud in rotary system of drilling for oil. The main purpose of Bentonite is to lubricate & cool the rotary cutting bits, carry away rock cutting fragments & to act as a seal against the escape of gas from the bore hole & to improve & prevent the hole from blowing out. Another function of such Bentonite based fluids is to condition the wall of the drill hole to prevent caving.Numerous particle size options are available in the lower micron area from a mean particle size of 2.5 to 4.0 microns. Information provided by Reade Advanced Materials. |
| BaTiSi3O9, taylorite, fuller's earth, Wyoming sodium bentonite, sodium montmorillonite, saponite, hectorite, hormite clay |
