fossil

Fossilized bone fragment, possibly mammalian long bone

Mineralized bone (commonly apatite, Ca₅(PO₄)₃(OH,F,Cl), replacing original bone)

AI-generated identification · may be incorrect

Brown, dense, irregular specimen with longitudinal fibrous texture and probable cortical-bone structure; luster is dull to earthy, hardness typically about 4–6 Mohs, with no obvious crystal cleavage. The image alone cannot confirm taxonomic identity or distinguish fossil bone from weathered modern bone.

Identified September 5, 2026More fossil →

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At a glance

Common name: Fossilized bone fragment, possibly mammalian long bone
Scientific name: Mineralized bone (commonly apatite, Ca₅(PO₄)₃(OH,F,Cl), replacing original bone)
Category: fossil
Identified: September 5, 2026
Method: Standard

AI Estimated Value

Typically $5–$50 for an unidentified fragment; $50–$500+ if well-preserved, identifiable, legally collected, and accompanied by provenance.

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

Buried bone can undergo permineralization and replacement by silica, calcite, or phosphate-bearing minerals over thousands to millions of years; age and locality require geological context or laboratory dating. It likely formed in a sedimentary deposit.

Uses & applications

Primarily a collecting, educational, and paleontological specimen; fossil bone may be used for display or research, but has little industrial or jewelry value unless exceptionally preserved or scientifically important.

Geological facts

The porous internal structure and layered cortical texture are characteristic clues, but surface weathering can obscure them. A clean broken or CT-examined section is much more diagnostic than the exterior.

Field identification & locations

Common in river gravels, deserts, badlands, caves, and sedimentary exposures worldwide; identify by visible vascular canals, spongy interior, and a heavier feel than ordinary wood. Avoid destructive testing or cleaning without expert guidance.