Know all about Hornfels and Greywacke properties here. All properties of rocks are important as they define the type of rock and its application. Hornfels belongs to Metamorphic Rocks while Greywacke belongs to Sedimentary Rocks.Texture of Hornfels is Granular, Platy whereas that of Greywacke is Clastic. Hornfels appears Dull and Greywacke appears Dull. The luster of Hornfels is shiny while that of Greywacke is dull. Hornfels is available in brown, dark greenish - grey, green, reddish brown colors whereas Greywacke is 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 Hornfels are cemetery markers, commemorative tablets, creating artwork and that of Greywacke are as armour rock for sea walls, petroleum reservoirs, sea defence, tombstones.