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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 report presents a thorough study of talc and pyrophyllite, covering both global and regional markets.
The overall global talc and pyrophyllite market is forecast to experience steady growth from 2011 onwards to reach extremely good volume results by the end of 2015.
Growth Opportunities for Talc and Pyrophyllite Lie Outside
In clay body formulas, felspars form eutectics, bringing clays, flint, talc, pyrophyllite, and other refractory materials into a vitreous state when heated.
com/research/ad3b76/talc_and_pyrophyll) has announced the addition of the "Talc and Pyrophyllite - Global Strategic Business Report" report to their offering.
Table 2: Global Pyrophyllite Production by Select Countries -
LONDON -- Talc and Pyrophyllite Market Review 2010 has been recently added by Market Publishers Ltd.
Alteration in the area is composed of silicification, pyritization, sericitization, alunite and pyrophyllite and is suggestive of a high sulfidation mineralizing system.