sedimentary

Red sandstone

Quartz-rich siliciclastic sandstone, likely ferruginous arkose or litharenite

AI-generated identification · may be incorrect

Fine- to medium-grained, reddish-brown, dull to slightly gritty; mainly quartz with feldspar and rock fragments, colored by iron-oxide cement. Hardness is approximately 6–7 for grains, with no obvious cleavage; bulk specific gravity is about 2.2–2.7.

Identified August 21, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed when sand accumulated in a terrestrial or shallow-marine environment, then compacted and cemented, probably during the Paleozoic–Mesozoic or younger. The red color indicates oxidation of iron-bearing minerals during deposition or later weathering.

Uses & applications

Used as building stone, paving, landscaping aggregate, and historically for walls and monuments; attractive pieces may be collected but are generally low-value.

Geological facts

The specimen shows granular texture and likely iron staining rather than crystalline growth. Its break is irregular, and the dark specks may be lithic fragments, biotite, or manganese/iron oxides.

Field identification & locations

Identify by rubbing the gritty surface, observing visible sand grains, and checking for weak layering; dilute acid should not fizz unless carbonate cement is present. Common in desert, fluvial, deltaic, and coastal sedimentary formations worldwide.