sedimentary

Red Sandstone

Arenite (Ferruginous Sandstone)

AI-generated identification · may be incorrect

Hardness: 6.5-7 (Mohs); Color: Red, reddish-brown, or orange; Luster: Dull/Earthy; Crystal Structure: Clastic/Granular; Specific Gravity: 2.2-2.8

Hardness: 6
Color: Red, reddish-brown, or orange
Luster: Dull/Earthy

Identified July 19, 2026More sedimentary →

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Physical properties

Hardness: 6.5-7 (Mohs); Color: Red, reddish-brown, or orange; Luster: Dull/Earthy; Crystal Structure: Clastic/Granular; Specific Gravity: 2.2-2.8

Formation & geological history

Formed by the accumulation and lithification of sand-sized mineral grains, primarily quartz, cemented by iron oxides like hematite or goethite. Typically formed in desert, river, or ocean environments over millions of years.

Uses & applications

Mainly used as a decorative building stone, in landscaping, and sometimes as a source of quartz for glass making if pure enough.

Geological facts

The red color is caused by the oxidation of iron minerals, similar to the process of rusting. Famous examples include the 'Red Rocks' of Colorado and the spectacular formations in Sedona, Arizona.

Field identification & locations

Identify by its gritty texture (feels like sandpaper) and distinct red layering or staining. Common in arid regions and ancient riverbeds. To test, try to scratch the surface; it should release individual sand grains.