sedimentary

Likely red sandstone or iron-rich volcanic rock

Probable ferruginous sandstone; exact identification requires testing

AI-generated identification · may be incorrect

Reddish-brown, fine-grained, dull and porous with rounded edges from weathering or tumbling. Likely Mohs hardness 5–7; composed mainly of quartz and feldspar with iron-oxide cement, though vesicular basalt is an alternative.

Identified August 26, 2026More sedimentary →

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Physical properties

Formation & geological history

If sandstone, it formed by burial and cementation of sand, with hematite producing the red color; ages may range from hundreds of millions to billions of years. The cavities could also indicate weathered volcanic scoria, formed from gas-rich lava.

Uses & applications

Common sandstone is used for building stone, paving, and aggregate; volcanic rock is used as lightweight aggregate and landscaping material. This small rounded specimen has little commercial value.

Geological facts

The image alone cannot reliably distinguish porous sandstone from weathered scoria or another iron-rich rock. A streak, acid, density, and close-grained examination would improve identification.

Field identification & locations

Check for visible sand grains and gritty texture (sandstone) versus abundant bubble cavities and a glassy groundmass (scoria). Common sources include red-bed terrains worldwide and volcanic regions; likely value is $1–$10 for an ordinary specimen, or up to $20 if unusually attractive or provenance-labeled.