Chemistry : Mg3Si4O10(OH)2, Magnesium Silicate Hydroxide Class : Silicates Subclass : Phyllosilicates Group : Clays and also The Montmorillonite / Smectite Group. Uses: An ornamental and heat, acid and electrically-resistant stone (soapstone) used as counter tops, electrical switchboards, carvings etc, used as an ingredient in paints, rubber, roofing materials, ceramics and insecticides. Most commonly known as the primary ingredient in talcum powder. Talc is an important industrial mineral. Its resistance to heat, electricity and acids make it an ideal surface f