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DEFINITION FOR TALC.

January 1, 1984

Talc is a naturally occurring single-phase mineral having the approximate chemical formula Mg//3Si//4O//1//0(OH)//2 and a specific type of crystal structure. Talc commonly forms by hydrothermal alteration of rocks rich in magnesium and iron (ultramafic rocks) and by low-grade thermal metamorphism of siliceous dolomites. The fact that talc often occurs in association with other minerals, or that its crystalline form may be platy, fibrous, acicular, or massive, does not modify its definition. The paper discusses variations in talc chemical composition and its crystal structure and describes its characteristic physical properties.

Publication Year 1984
Title DEFINITION FOR TALC.
Authors Malcolm Ross
Publication Type Conference Paper
Publication Subtype Conference Paper
Index ID 70013412
Record Source USGS Publications Warehouse