sedimentary

Sandstone

Arenite (SiO2 primarily)

Hardness: 6-7 (individual grains), Color: Reddish-brown, Luster: Dull or earthy, Crystal structure: Primarily clastic and granular, Cleavage: None, Specific gravity: 2.2-2.8

Identified June 19, 2026More sedimentary →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 6-7 (individual grains), Color: Reddish-brown, Luster: Dull or earthy, Crystal structure: Primarily clastic and granular, Cleavage: None, Specific gravity: 2.2-2.8

Formation & geological history

Formed by the accumulation and cementation of sand-sized mineral grains or rock fragments, typically through the process of lithification at low temperatures and pressures.

Uses & applications

Commonly used in construction for building stone, floor tiles, and paving. Also used as a reservoir rock for oil, gas, and groundwater.

Geological facts

Sandstone represents about 20-25% of all sedimentary rocks. It often preserves fossils and ripple marks that indicate ancient environmental conditions like desert dunes or riverbeds.

Field identification & locations

Identify by its characteristic 'sandpaper' feel and visible sand grains. Found globally in basins, riverbeds, and cliff faces. Best identified in the field by checking if individual sand grains can be scratched off with a knife.