sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

Hardness: 6-7 Mohs; Color: reddish-brown; Luster: dull/earthy; Texture: granular with visible pores; Composition: primarily quartz grains coated with iron oxides (hematite).

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

Identified July 3, 2026More sedimentary →

Explore Red 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; Texture: granular with visible pores; Composition: primarily quartz grains coated with iron oxides (hematite).

Formation & geological history

Formed through the accumulation and cementation of sand-sized mineral grains or rock fragments. The red color suggests deposition in an oxygen-rich terrestrial environment, such as a desert or river floodplain, where iron minerals oxidize.

Uses & applications

Commonly used as a building material, decorative stone in landscaping, and in the manufacturing of glass or for industrial abrasives if high in silica.

Geological facts

The red color is caused by the presence of hematite (iron oxide). Many of the world's most famous natural landscapes, like the Grand Canyon or Sedona, Arizona, are composed of massive layers of red sandstone.

Field identification & locations

Identify by the sandpaper-like feel and the reddish rub-off. Found globally in basins and desert regions. Look for bedding planes or cross-bedding indicating ancient dunes or water currents.