Know all about Siltstone and Soapstone properties here. All properties of rocks are important as they define the type of rock and its application. Siltstone belongs to Sedimentary Rocks while Soapstone belongs to Metamorphic Rocks.Texture of Siltstone is Clastic whereas that of Soapstone is Polished. Siltstone appears Rough and Soapstone appears Dull, Banded and Foilated. The luster of Siltstone is dull while that of Soapstone is greasy. Siltstone is available in brown, red, reddish brown colors whereas Soapstone is available in black, black to grey, green, grey colors. The commercial uses of Siltstone are raw material for the manufacture of mortar, soil conditioner and that of Soapstone are cemetery markers, creating artwork, gemstone, jewelry, manufacture of soap, solvents, dyes, plastics and fibres, production of lime, source of magnesia (mgo).