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Related to Pyrophyllite: talc


AlSi2O5(OH) A white, greenish, gray, or brown phyllosilicate mineral that resembles talc and occurs in a foliated form or in compact masses in quartz veins, granites, and metamorphic rocks. Also known as pencil stone.



a mineral of the phyllosilicate class, with chemical composition Al2[Si4O10](OH)2; it contains admixtures of MgO, FeO, and Fe2O3. Pyrophyllite crystallizes in the mono-clinic system. It generally occurs in the form of foliate or compact scaly aggregates that are pale yellow, yellowish, or white in color. Pyrophyllite exhibits perfect cleavage. Greasy to the touch, it resembles talc. It has a hardness of 1–1.5 on Mohs’ scale and a density of 2,840 kg/m3.

Pyrophyllite deposits are usually associated with metamorphic rocks, in which the mineral forms packets of pyrophyllite slate or compact agalmatolite aggregates. It sometimes occurs in hydrothermal quartz and ore veins. Pyrophyllite is both fire- and acid-resistant. It is used commercially as a highly aluminiferous raw material for refractory products and as a chemically stable and insulating material.

References in periodicals archive ?
5, and Al2O3 recovery is about 79% which implies that DTAL could be the right choice for cationic collectors for mineral floatation of aluminum-bearing silicates like pyrophyllite, illite and kaolinite and this choice makes possible the desilication of diasporic bauxite ore [8].
2001, "Adsorption of cyanide from aqueous solutions at pyrophyllite surface," Sep.
Asia is estimated to account for over 40% of world talc consumption and for over 85% of pyrophyllite consumption.
The Talc and Pyrophyllite Market Review is an absolutely essential resource for anyone interested in detailed information on the reviewed market.
The pyrophyllite product is described as a natural blend of talc-like platy particles and irregular, blocky particle shapes.
Montmorillonite is a derivative of pyrophyllite and has a 2:1 layer structure consisting of two fused silica tetrahedral sheets sandwiching an octahedral sheets of alumina (see Fig.
Hand building, jiggering and Ram press bodies have greater percentages of non plastic clays such as fireclay, kaolins and stoneware clays and higher percentages of non plastic materials such as flint, feldspar and pyrophyllite.
Other, less common mineral species that have been reported from the Klein Spitzkoppe occurrences include bixbyite, chabazite, columbite, euxenite-(Y), gibbsite, nacrite, opal (hyalite), pyrophyllite, talc, ferberite and zircon.
Extender pigments (talc, wollastonite, pyrophyllite and kaolin clay)
Two samples from the high-grade mantos at El Toro consist of a mixture of fine-grained pyrophyllite and lesser amounts of kaolinite.
LONDON -- In terms of sales talc and pyrophyllite are largely dependent on the manufacturing sector, automotive industry being the key force here.
The water-swellable fillers can be bentonite, lignite, alumina trihydrate, barytes, calcium carbonate, chlorite, clays, pyrophyllite, talc, polyacrylic acid, polyacrylamide, sodium polyacrylate, cellulose esters, ethylene vinyl chloride, acrylic resins, alkyd resins, polyethylene oxide, collagens, gelatins, or ethylene acrylic acid copolymers.