abstract appearance background brown colored coloring colors coloured colouring colours conglomerate contours contrast contrasts cracks fissures flaws grit gritty layered layers levels light lines mica natural rock rock-face rockface rocky rough rugged shade shadows shape shapes silicate stone strata stratum sunlight sunny sunshine surfaces texture textured textures veins wallpaper blocks cracked solid split strength surface close-up crack fissure granite composition crystalline feldspar grain grained grains grainy gray grey igneous-rock mineralogy minerals pitted quartz shaped stonework worked