sedimentary

Fossilized Angel Wing Shell

Cyrtopleura costata

Hardness: 2.5-3.5 (Mohs scale), Color: Creamy white to grayish-white, Luster: Dull or chalky, Structure: Fragile thinned shell with radiating ribs and tooth-like serrations, Mineral composition: Calcium carbonate (Calcite/Aragonite).

Hardness: 2

Identified April 11, 2026More sedimentary →

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Physical properties

Formation & geological history

Formed through the process of permineralization or as a trace fossil preservation in marine sedimentary layers. Specifically found in Pliocene and Pleistocene deposits (approx. 10,000 to 5 million years old) where soft-bottom marine environments existed.

Uses & applications

Used primarily for educational study, paleontology collections, and as decorative coastal display pieces.

Geological facts

The Angel Wing clam is a piddock that burrows as deep as three feet into sand or mud. They are so named because the two valves of the shell together look like the wings of an angel. Unlike many other clams, they cannot retract their large fleshy siphon into the shell.

Field identification & locations

Identify by its distinctive elongated wing shape with prominent ribs that resemble feathers. Commonly found in coastal areas of the Atlantic and Gulf coasts of North America, particularly in fossil-rich shell beds of Florida.

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