fossil

Fossil shell or shell fragment

Likely a calcareous bivalve or gastropod fragment; precise identification requires locality and microscopy

AI-generated identification · may be incorrect

Pale cream to pink, matte, and irregularly triangular, with fine growth lines and layered fibrous texture. Likely calcite/aragonite; Mohs hardness about 3–4, with weak to moderate cleavage and specific gravity roughly 2.6–2.9; dilute acid may effervesce.

Identified August 19, 2026More fossil →

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Physical properties

Formation & geological history

A biological shell formed in marine or freshwater conditions, later buried and mineral-preserved or partially recrystallized. Geological age cannot be determined from the photograph alone.

Uses & applications

Primarily a natural-history or educational specimen; intact examples may be used in jewelry, décor, or collections, while fragments have little industrial value.

Geological facts

The visible curved growth bands are characteristic of shell growth rather than igneous or metamorphic texture. Pink coloration can result from original shell pigments, staining, or mineral alteration.

Field identification & locations

Look for concentric growth lines, a shell-like layered structure, and acid reaction; compare with local fossil guides. Common in limestone, coastal deposits, river gravels, and shell beds.