Sandstone is a kind of sedimentary rockwhich is composed mainly of sand-size mineral or rock grains. Most sandstone is composedof quartz and/or feldspar because these are the most common minerals in theEarth's crust. Like sand, sandstone may come in any color, but the most commoncolors are tan, brown, yellow, red, gray and white. Since sandstone beds oftenform highly visible cliffs and other topographic features, certain colors ofsandstone have been strongly identified with certain regions.