fossil

Polished fossil bone fragment

Fossilized bone, likely mammalian or reptilian; exact taxon cannot be determined from the image

AI-generated identification · may be incorrect

Dark brown to black, glossy, elongated and polished with parallel longitudinal grooves and cellular-looking texture. Fossil bone commonly has Mohs hardness about 4–6, dense microcrystalline apatite, and no cleavage; the apparent luster is enhanced by polishing.

Identified September 5, 2026More fossil →

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At a glance

Common name: Polished fossil bone fragment
Scientific name: Fossilized bone, likely mammalian or reptilian; exact taxon cannot be determined from the image
Category: fossil
Identified: September 5, 2026
Method: Standard

AI Estimated Value

About $5–$30 for a small common polished fragment; $50–$200+ if unusually attractive, well-provenanced, or taxonomically identifiable.

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

Mineral-rich groundwater replaced or infilled original bone tissue, commonly with silica, calcite, or iron/manganese oxides, during diagenesis. Age and locality cannot be established visually; such specimens may range from Cenozoic to much older.

Uses & applications

Used mainly as a decorative or educational fossil specimen, pendant, or carving material; it has little industrial use and is not a conventional gemstone.

Geological facts

The ridged texture may represent preserved cortical bone structure, but it could also be a polished fragment of fossil wood or another organic fossil. A microscope, density, hardness, and locality data are needed for confident identification.

Field identification & locations

Field clues include visible porous or fibrous internal structure, unusually dense weight, and color penetration rather than surface-only staining; acid testing should be avoided on valuable material. Fossil bone occurs worldwide in sedimentary deposits, especially river, lake, and cave sediments.