mineralized fossil

Fossilized Chiton (Polyplacophora)

Polyplacophora (fossilized valves)

AI-generated identification · may be incorrect

Hardness: 3-4 (calcitic); Color: Pale grey to tan; Luster: Dull to slightly sparkling; Structure: Segmented aragonite or calcite plates; Cleavage: None (organic structure).

Hardness: 3-4 (calcitic)
Color: Pale grey to tan
Luster: Dull to slightly sparkling

Identified June 28, 2026More mineralized fossil →

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Physical properties

Hardness: 3-4 (calcitic); Color: Pale grey to tan; Luster: Dull to slightly sparkling; Structure: Segmented aragonite or calcite plates; Cleavage: None (organic structure).

Formation & geological history

Formed through permineralization of the overlapping shells (valves) of a marine mollusk. These typically date from the Paleozoic to the Holocene, frequently found in limestone or maritime sedimentary deposits.

Uses & applications

Primarily used for paleontological study, educational collections, and natural history specimens.

Geological facts

Chitons are often called 'sea cradles.' While their soft bodies decay, their eight interlocking valves can fossilize together, appearing like a small armored pill bug or trilobite component.

Field identification & locations

Identify by the distinct curved, overlapping segmented plates and oval shape. Commonly found in coastal sedimentary rocks or ancient reef deposits. Search for them in limestone outcrops.