Know all about Greywacke and Sandstone properties here. All properties of rocks are important as they define the type of rock and its application. Greywacke and Sandstone belong to Sedimentary Rocks.Texture of Greywacke is Clastic whereas that of Sandstone is Clastic, Granular, Rough. Greywacke appears Dull and Sandstone appears Rough. The luster of Greywacke and Sandstone is dull. Greywacke and Sandstone are available in beige, black, brown, colourless, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors. The commercial uses of Greywacke are as armour rock for sea walls, petroleum reservoirs, sea defence, tombstones and that of Sandstone are an oil and gas reservoir, in aquifers, petroleum reservoirs, soil conditioner, source of magnesia (mgo), tombstones, used in aquariums.