fossil

Operculum (Cat's Eye Shell)

Biogenic Aragonite/Calcite (CaCO3)

AI-generated identification · may be incorrect

Hardness 3.0-3.5; porcelain-white to iridescent pearly luster; planar spiral structure; specific gravity ~2.7-2.9.

Identified October 13, 2026More fossil →

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Physical properties

Hardness 3.0-3.5; porcelain-white to iridescent pearly luster; planar spiral structure; specific gravity ~2.7-2.9.

Formation & geological history

Formed biologically as the protective calcareous 'trapdoor' of marine gastropods (such as Turbinidae), often found subfossilized in coastal sands.

Uses & applications

Used in ornamental jewelry, decorative inlays, and as beachcomber collector charms.

Geological facts

Commonly known as 'Shiva's Eye' or 'Cat's Eye', it is widely regarded as a protective talisman in maritime folklore.

Field identification & locations

Identified by its circular to oval shape, spiraling growth lines on the flat side, and effervescence in dilute acid; found washed up on tropical coastlines.

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