Soapstone is a talc-schist, which is a type of metamorphic rock. It is composed largely of the magnesium-rich mineral talc. It is produced by dynamothermal metamorphism and metasomatism, which occur in subduction zones, changing rocks by heat and pressure, with influx of fluids but without melting. It has been a carving medium for thousands of years.
Samples of soapstone
A block of talc
Mythological figures carved in soapstone by Kayasark, Inuit carver, held in the Honolulu Academy of Arts
The 21st-century BC statue of Iddi-Ilum of Mari, Syria, is made of soapstone
Talc, or talcum, is a clay mineral composed of hydrated magnesium silicate, with the chemical formula Mg3Si4O10(OH)2. Talc in powdered form, often combined with corn starch, is used as baby powder. This mineral is used as a thickening agent and lubricant. It is an ingredient in ceramics, paints, and roofing material. It is a main ingredient in many cosmetics. It occurs as foliated to fibrous masses, and in an exceptionally rare crystal form. It has a perfect basal cleavage and an uneven flat fracture, and it is foliated with a two-dimensional platy form.
Talc
A block of talc
View of trioctahedral sheet of talc. Yellow spheres are hydroxyl; blue are magnesium. Apical oxygen binding sites are white.
Talc crystal viewed along the [100] axis, looking along the layers of the crystal