Sandstone is a sedimentary rock composed of sand-sized grains of mineral, rock or organic material. It also contains a cementing material that binds the sand grains together and may contain a matrix of silt- or clay-size particles that occupy the spaces between the sand grains.
Sandstone is one of the most common types of sedimentary rock and is found in sedimentary basins throughout the world. It is often mined for use as a construction material or as a raw material used in manufacturing. In the subsurface, sandstone often serves as an aquifer for groundwater or as a reservoir for oil and natural gas.
The grains in a sand stone can be composed of mineral, rock or organic materials. Which and in what percentage depends upon their source and how they have suffered during transport.
Mineral grains in sandstones are usually quartz. Sometimes the quartz content of these sands can be very high – up to 90% or more. These are sands that have been worked and reworked by wind or water and are said to be “mature”. Other sands can contain significant amounts of feldspar and if they came from a source rock with a significant quartz content they are said to be “immature”.