Colorful Shard!

Sandstone is a clastic sedimentary rock composed mainly of sand-sized (0.0625 to 2 mm) silicate grains, cemented together by another mineral. Sandstones comprise about 20–25% of all sedimentary rocks.
Most sandstone is composed of quartz or feldspar, because they are the most resistant minerals to the weathering processes at the Earth's surface. Like uncemented sand, sandstone may be imparted any color by impurities within the minerals, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black. Because sandstone beds can form highly visible cliffs and other topographic features, certain colors of sandstone have become strongly identified with certain regions, such as the red rock deserts of Arches National Park and other areas of the American Southwest.

Rock formations composed of sandstone usually allow the percolation of water and other fluids and are porous enough to store large quantities, making them valuable aquifers and petroleum reservoirs.

Quartz-bearing sandstone can be changed into quartzite through metamorphism, usually related to tectonic compression within orogenic belts.