Sandstone is a type of rock composed mainly of sand that has been "bonded" together by pressure or by minerals. The sand commonly consists of grains of quartz, feldspar, and other minerals. It may also include organic matter or rock fragments. The minerals that cement the grains include quartz, pyrite, or calcite.

The colour of sandstone ranges from cream or grey to red, brown, or green, depending on the cements and impurities in the sand. Brownstone, reddish-brown sandstone, was once widely used to build houses. Sandstone was a common building material for larger structures before reinforced concrete came into use in the middle to late 1800's.

Sandstone 1 :
Sandstone is a rock composed of sand sized grains of quartz (SiO₂) that have been lithified or cemented together. Sandstone forms the most prominent layers which creates the characteristic bluffs along the Bryant and its tributaries. Sandstone also occurs as discontinuous layers and lenses.

The sandstone layers are good aquifers and springs are usually found where it is cut by stream valleys. The sandstone layers typically weather to a medium-light gray outcrop. On freshly broken surfaces the sandstone varies from white through shades of tan and reddish brown. The red tints are due to iron oxide within the cement that holds the sand grains together.

Weathering of the sandstone produces the sand of the sand bars along the creek channels and the sandy soils of the rich bottomlands along the Bryant.

Textures within the sandstone layers such as cross-bedding, ripple marks, and mud cracks, are clues to the origin of the layers as shallow, intertidal or delta sediments.

Sandstone 2 :
Sandstone is a sedimentary stone that is typically the result quartzitic stones being eroded and re deposited by either wind or water. River beds, ocean beaches and sand dunes will all eventually become sandstone. Sandstone is typically the youngest of the quartz based stones. As sandstone is subjected to heat and pressure, it will eventually turn into quartzite, which is an incredibly hard and dense material.

Since most of these stones are taken from the ground in individual layers, they are typically used as flooring or paving materials. Most flagstone used in residential applications here in New Mexico is sandstone. Most sandstones and quartzites have a "natural cleft" finish, meaning the finished surface is the way the stone came out of the ground. Some sandstones are honed for a smoother finish. Most sandstones are suitable for both interior and exterior application.