Know all about Greywacke and Coquina properties here. All properties of rocks are important as they define the type of rock and its application. Greywacke and Coquina belong to Sedimentary Rocks.Texture of Greywacke is Clastic whereas that of Coquina is Clastic. Greywacke appears Dull and Coquina appears Layered, Banded, Veined and Shiny. The luster of Greywacke is dull while that of Coquina is dull to vitreous to submetallic. Greywacke is available in beige, black, brown, colourless, cream, dark brown, green, grey, light green, light to dark grey, pink, red, white, yellow colors whereas Coquina is available in beige, buff, orange colors. The commercial uses of Greywacke are as armour rock for sea walls, petroleum reservoirs, sea defence, tombstones and that of Coquina are creating artwork.