Know all about Siltstone and Shoshonite properties here. All properties of rocks are important as they define the type of rock and its application. Siltstone belongs to Sedimentary Rocks while Shoshonite belongs to Igneous Rocks.Texture of Siltstone is Clastic whereas that of Shoshonite is Porphyritic. Siltstone appears Rough and Shoshonite appears Dull. The luster of Siltstone and Shoshonite is dull. Siltstone is available in brown, red, reddish brown colors whereas Shoshonite is available in brown- black, dark brown colors. The commercial uses of Siltstone are raw material for the manufacture of mortar, soil conditioner and that of Shoshonite are cemetery markers, creating artwork.