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