sedimentary

Banded iron formation (specimen, possibly hematite–jasper)

Banded iron formation; chiefly hematite (Fe₂O₃), magnetite (Fe₃O₄), and silica (chert/quartz), with possible limonite/goethite staining

AI-generated identification · may be incorrect

Metallic to earthy luster; silver-gray, rusty orange, and brown bands with uneven fracture and strongly layered texture. Hardness is roughly 5–6.5 Mohs, depending on quartz and iron oxides; generally dense and weakly magnetic if magnetite is present.

Identified September 6, 2026More sedimentary →

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At a glance

Common name: Banded iron formation (specimen, possibly hematite–jasper)
Scientific name: Banded iron formation; chiefly hematite (Fe₂O₃), magnetite (Fe₃O₄), and silica (chert/quartz), with possible limonite/goethite staining
Category: sedimentary
Identified: September 6, 2026
Method: Standard

AI Estimated Value

About $10–$50 for a common hand specimen; $50–$150 if unusually large, strongly banded, or attractively polished.

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

Chemical sediment deposited in ancient oceans, commonly 2.5–1.8 billion years ago, when dissolved iron precipitated as oxygen levels increased; later compacted and lithified. The folded or streaked appearance reflects deformation and weathering.

Uses & applications

Primarily an iron ore and occasionally used as an ornamental stone, paperweight, or educational specimen; rarely suitable for jewelry unless polished.

Geological facts

Alternating iron-rich and silica-rich layers are diagnostic, and red-orange colors commonly result from oxidized iron minerals. The specimen’s bright red painted mark appears to be an inventory or display label, not natural mineral coloration.

Field identification & locations

Look for dense, parallel iron/silica banding, rusty weathering, and possible attraction to a magnet. Common in the Lake Superior region, Western Australia, South Africa, India, and Brazil.