Sandstone

Sandstone is a type of rock that is primarily composed of sand-sized minerals or rock grains. Most sandstone is composed of quartz and/or feldspar because these are the most common minerals in the Earth's crust. Like sand, sandstone may be any color, but the most common colors are tan, brown, yellow, red, grey, pink, white, and black.

Formation

Sandstone is formed from sediment that has been settled and compacted, and then lithified into rock. The process of formation includes:

• Erosion: The source material for sandstone is the erosion product of pre-existing rocks.
• Transportation: The eroded material is then transported by water, wind, or ice to the place where the sediment is deposited.
• Deposition: The sediment is deposited in places such as beaches, river deltas, or sand dunes.
• Compaction: Over time, more and more sediment is deposited, causing the lower layers to be compacted by the weight of the layers above.
• Cementation: Minerals in the water that the sediment is in can act as a glue or cement, causing the sediment grains to stick together and form rock.

Types of Sandstone

There are many different types of sandstone, including:

• Arkose: This is a type of sandstone that is rich in feldspar.
• Greywacke: This type of sandstone is a variety of sandstone that has a large amount of clay.
• Quartz Sandstone: This is a type of sandstone that is almost entirely composed of quartz grains.

Uses

Sandstone has been used for domestic construction and housewares since prehistoric times, and continues to be used. It is often used for construction because it is easy to work with and makes for a good building material. It is also used in the production of glass and ceramics, as well as in the petroleum industry as a reservoir for oil and gas.

See Also

• Sedimentary rock
• Erosion
• Deposition