sandstone
Sedimentary rock consisting of sand or quartz grains consolidated and compacted together, typically reddish in color, although yellow and brown versions are also common. Rock formations composed of sandstone are relatively porous, allowing for percolation of water and dynamic erosion by both water and wind.
Sandstone often forms dramatically colored and shaped cliffs and other geologic formations, such as the iconic stone monoliths in Monument Valley, Utah. The rock outcropping of El Morro, on the Zuni Reservation, is composed of yellowish-gray white sandstone known as Zuni Sandstone.