sedimentary

Red Sandstone

Arenite (primarily Quartz with Iron Oxide)

AI-generated identification · may be incorrect

Hardness: 6-7 (Mohs scale); Color: Reddish-brown to maroon; Luster: Dull/Earthy; Crystal Structure: Clastic (granular texture); Cleavage: None; Specific Gravity: 2.2-2.8

Hardness: 6-7 (Mohs scale)
Color: Reddish-brown to maroon
Luster: Dull/Earthy

Identified April 13, 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 scale); Color: Reddish-brown to maroon; Luster: Dull/Earthy; Crystal Structure: Clastic (granular texture); Cleavage: None; Specific Gravity: 2.2-2.8

Formation & geological history

Formed from the accumulation of sand-sized grains (mostly quartz) deposited in deserts, river beds, or basins. The red color comes from the oxidation of iron minerals (hematite) during lithification. Most abundant in Paleozoic and Mesozoic era formations.

Uses & applications

Used extensively as building stone (brownstone), paving material, decorative garden stone, and in the production of glass (if high quartz purity).

Geological facts

Red sandstone is famous for creating the iconic landscapes of the American Southwest, such as the Grand Canyon and Zion National Park. It is often referred to as 'Old Red Sandstone' in geological history.

Field identification & locations

Identify by its gritty, sandpaper-like feel and visible grains. Often displays bedding planes or cross-bedding. Found globally in arid or former river delta regions.