sedimentary

Sandstone

Arenite (SiO2 with minor iron oxides)

Hardness: 6-7 Mohs; Color: reddish-brown; Luster: dull/earthy; Crystal Structure: Clastic (sand-sized grains); Cleavage: none; Specific Gravity: 2.2-2.8

Hardness: 6-7 Mohs
Color: reddish-brown
Luster: dull/earthy

Identified July 14, 2026More sedimentary →

Explore Sandstone in the encyclopedia →

Identify your own rocks.

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

App Store Google Play

Physical properties

Hardness: 6-7 Mohs; Color: reddish-brown; Luster: dull/earthy; Crystal Structure: Clastic (sand-sized grains); Cleavage: none; Specific Gravity: 2.2-2.8

Formation & geological history

Formed via the accumulation and cementation of sand-sized mineral particles or rock fragments, typically in desert, river, or coastal environments over millions of years.

Uses & applications

Commonly used as a building material, paving stone, and in the manufacturing of glass and grindstones. Small specimens are used for educational purposes.

Geological facts

Sandstone can store large quantities of water or oil in its pores, making it a critical aquifer or petroleum reservoir. The color is often derived from iron oxide (rust).

Field identification & locations

Identify by its gritty, sandpaper-like feel and visible grains. Found worldwide in sedimentary basins, canyons, and cliffs. Small pebbles are common in riverbeds and gardens.