sedimentary

Rounded iron-rich cobble (likely lateritic sandstone or ironstone)

Ferruginous sandstone/ironstone; chiefly quartz (SiO₂) with iron oxides, especially hematite (Fe₂O₃) and goethite (FeO(OH))

AI-generated identification · may be incorrect

Brown to rusty, dull earthy luster, fine-grained and strongly rounded from weathering or transport; apparent hardness about 5–6, commonly with no visible cleavage. Exact identification would benefit from a streak, magnetism, and hardness test.

Identified September 7, 2026More sedimentary →

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At a glance

Common name: Rounded iron-rich cobble (likely lateritic sandstone or ironstone)
Scientific name: Ferruginous sandstone/ironstone; chiefly quartz (SiO₂) with iron oxides, especially hematite (Fe₂O₃) and goethite (FeO(OH))
Category: sedimentary
Identified: September 7, 2026
Method: Standard

AI Estimated Value

Typically $1–$10 as an ordinary cobble; approximately $10–$30 if unusually dense, attractive, or demonstrably mineralized.

Not an official valuation

AI estimate for general interest only — not an appraisal. Actual value depends on condition, provenance, and market demand. Verify with a professional before buying, selling, or insuring.

This identification was generated by AI and may contain errors. Verify important details before relying on them — and never use an AI result to judge whether a specimen is safe to handle. Read the full disclaimer

Physical properties

Formation & geological history

Likely formed by cementation or weathering that concentrated iron oxides, then became rounded in a stream or gravel deposit. Such material may be Quaternary surface gravel over older sedimentary rocks; age cannot be determined from the photograph.

Uses & applications

Usually a common geological specimen with little commercial value; ironstone can be an iron ore, while ferruginous sandstone may be used locally as aggregate or decorative stone.

Geological facts

The dark central patch may be concentrated hematite or a weathered surface, but it is not diagnostic. It does not visibly resemble a meteorite: the rusty, porous earthy surface is more typical of terrestrial ironstone.

Field identification & locations

Near 34.7°N, 50.9°E, weathered sedimentary rocks and iron-rich gravels are plausible. Test an inconspicuous area: hematite gives a red-brown streak, goethite a yellow-brown streak; a magnet may show weak attraction, and a steel nail should barely scratch it.