human
Can you tell me about some of the different kinds of sandstone?
assistant
Sandstone is a sedimentary rock composed of sand-sized grains. It can be formed from a variety of materials, including quartz, feldspar and calcite. Sandstone typically takes on a range of colors due to its mineral composition, but it can also be gray or brown in color. Sandstone can vary greatly in texture, depending on how the grains were arranged when they were deposited. This can include smooth, rippled, cross-bedded, or even contorted layers.