Know all about Gneiss and Siltstone properties here. All properties of rocks are important as they define the type of rock and its application. Gneiss belongs to Metamorphic Rocks while Siltstone belongs to Sedimentary Rocks.Texture of Gneiss is Banded, Foliated, Platy whereas that of Siltstone is Clastic. Gneiss appears Foliated and Siltstone appears Rough. The luster of Gneiss and Siltstone is dull. Gneiss is available in black, brown, pink, red, white colors whereas Siltstone is available in brown, red, reddish brown colors. The commercial uses of Gneiss are cemetery markers, jewelry, tombstones, used in aquariums and that of Siltstone are raw material for the manufacture of mortar, soil conditioner.