fossil

Possible fossilized bone fragment

Fossil bone, composition primarily carbonate-hydroxylapatite [Ca₅(PO₄)₃(OH)]

AI-generated identification · may be incorrect

Pale cream-gray, weathered and porous with rusty iron-oxide staining; dull to slightly earthy luster, irregular fracture, and typically Mohs hardness about 4–5. The tapered shape and possible cortical/medullary texture are consistent with bone, though the image alone cannot confirm it.

Identified August 19, 2026More fossil →

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Physical properties

Formation & geological history

Mineralized bone forms when original organic material is replaced or impregnated by apatite, silica, or calcite during burial; age may range from Recent subfossil to millions of years. Common settings include river gravels, caves, deserts, and sedimentary rocks.

Uses & applications

Usually collected as a fossil or educational specimen; some fossil bone is polished for décor and jewelry. It has little industrial value.

Geological facts

Fossil bone can preserve vascular channels and growth structure, while color commonly reflects groundwater minerals. A professional identification may require microscopy or testing for bone microstructure.

Field identification & locations

Look for porous internal texture, longitudinal grain, and a denser outer cortex; compare with ordinary limestone, wood, or modern bone. Common in sedimentary deposits worldwide, especially the western United States, Africa, and Australia.