fossil

Fossil gastropod shell

Calcareous mollusk shell, chiefly aragonite or calcite (likely a large marine gastropod)

AI-generated identification · may be incorrect

Hardness about 3–4 Mohs; white, opaque, nacreous to dull luster, spiral whorls, ribs, and a pointed spire. The shell is biogenic calcium carbonate rather than a crystalline rock, and appears weathered or partially mineralized.

Identified September 5, 2026More fossil →

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Physical properties

Formation & geological history

Formed by a marine gastropod, then buried and preserved in carbonate-rich sediment; fossilization may replace aragonite with calcite. Exact geological age cannot be determined from the photograph and may range from Cenozoic to Recent-looking shell material.

Uses & applications

Primarily a collecting, educational, and decorative specimen; fossil shells can be used in displays and paleontological study, but this piece has little industrial or jewelry value.

Geological facts

The visible spiral geometry and repeated growth lines are characteristic of gastropods. White coloration may result from bleaching, weathering, or mineral alteration after burial.

Field identification & locations

Identify by the coiled whorls, aperture, growth lines, and solid carbonate shell; distinguish it from a modern shell by mineral replacement, matrix attachment, and fossil wear. Similar specimens occur in marine limestone, coastal deposits, and fossil beds worldwide.