fossil

Fossilized wood or bone fragment

Indeterminate permineralized organic fossil; possibly silicified wood or fossil bone

AI-generated identification · may be incorrect

Tan-brown, fine-grained, matte to slightly earthy surface with dark concentric/irregular markings. Hardness and composition cannot be determined reliably from the image; fossil wood commonly contains quartz (Mohs 7), while bone may contain apatite (Mohs 5).

Identified September 2, 2026More fossil →

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Physical properties

Formation & geological history

A fossil formed when buried organic tissue was gradually mineral-replaced or pore-filled, commonly by silica, calcite, or iron minerals over millions of years. The visible pattern is insufficient to establish its geological age.

Uses & applications

Primarily a collector, educational, and lapidary specimen; silicified wood may be polished for ornaments, while fossil bone is rarely used commercially.

Geological facts

The central ring-like marking could represent wood grain, a growth structure, or a bone cross-section, but it is not diagnostic from this photograph alone.

Field identification & locations

Look for cellular wood texture, recognizable bone pores, mineral infill, and a heavy, stone-like feel; a fresh broken or polished surface and hardness testing help distinguish it. Common examples occur in sedimentary basins worldwide, including the western United States.