Talc: Student Name Abstract Talc is a phyllosilicate mineral known for having a hardness of one. It is a monoclinic mineral and occurs as a hydrothermal alteration of magnesium silicates that lack aluminum. Talc can occur in many different colors but is commonly light green or white and often has a greasy, “soapy” texture to it, giving it the common name soapstone. It forms closely with pyrophyllite and is often associated with asbestos minerals. Talc is an important industrial mineral that is mined using open-pit mining techniques in the United States. Talc consumed in the U.S. is used for ceramics, paint, paper, cosmetics, as well as other industrial uses. General Information on Talc ± Known for being the softest mineral on Moh’s Hardness Scale ± Can also have a trigonal crystal system ± A Phyllosilicate with a 2:1 ratio ± Can form through replacement of dolomitic marble by way of magnesium and silica rich hydrothermal water: CaMg(CO 3 ) 2 + 4 SiO 2 + H 2 O Î Mg 3 Si 4 O 10 (OH) 2 +3CO2 + Ca(CO 3 ) ± Can form through hydrothermal alteration of mafic rocks in which magnesite reacts with silica and water to form talc: MgCO 3 + 4SiO 2 + H 2 O Î
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