Rock Identifier
Fossilized bone fragment (probable large mammal limb bone) (Mineral-replaced or permineralized bone; exact taxon cannot be determined from the image) — fossil
fossil

Fossilized bone fragment (probable large mammal limb bone)

Mineral-replaced or permineralized bone; exact taxon cannot be determined from the image

AI-generated identification · may be incorrect

Tan-brown, porous, matte specimen with rounded contours and possible cortical texture; bone typically has Mohs hardness about 3–5, specific gravity roughly 2.0–3.0, and no consistent cleavage. The dark circular marks may be pores, weathering pits, or staining.

Identified More fossil
Explore Fossilized bone fragment (probable large mammal limb bone) in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

Physical properties

Tan-brown, porous, matte specimen with rounded contours and possible cortical texture; bone typically has Mohs hardness about 3–5, specific gravity roughly 2.0–3.0, and no consistent cleavage. The dark circular marks may be pores, weathering pits, or staining.

Formation & geological history

Originally formed as biological bone, then buried and mineralized through groundwater permineralization, commonly by silica, calcite, or iron minerals. Its geological age and species are indeterminate without locality and microscopic or chemical analysis.

Uses & applications

Primarily a fossil-collecting and educational specimen; occasionally used in display, replicas, and lapidary work if sufficiently mineralized. It has little commercial value unless provenance, rarity, or diagnostic anatomy is established.

Geological facts

The elongated shape and apparent porous structure are more consistent with bone than ordinary rock, but the photograph cannot exclude weathered wood, concretion, or a manufactured cast.

Field identification & locations

Inspect broken or sawn surfaces for a cellular, honeycomb-like interior and compare density with modern bone; avoid acid or destructive testing. Fossil bones occur worldwide in sedimentary deposits, especially river, lake, and floodplain sediments.