fossil

Operculum shell (often called "Shiva's Eye" or "Cat's Eye")

Operculum of a gastropod (e.g., Turbinidae family), primarily Calcium Carbonate (CaCO3) in the form of aragonite.

AI-generated identification · may be incorrect

Hardness: ~3.5 on Mohs scale. Color: Brown, reddish, orange, and white concentric bands. Luster: Vitreous to pearly. Crystal structure: Aragonite (orthorhombic). It has a flat or slightly convex side with a distinctive spiral or concentric circular pattern.

Hardness: ~3
Color: Brown, reddish, orange, and white concentric bands
Luster: Vitreous to pearly

Identified July 23, 2026More fossil →

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Physical properties

Formation & geological history

Formed biogenically by marine sea snails as a protective "trapdoor" to close the opening of their shell when retracted. Commonly found on beaches worldwide, especially in tropical and subtropical regions.

Uses & applications

Often used in jewelry making (pendants, rings, bracelets) due to its striking pattern and durability. Also collected as a beachcombing treasure and sometimes used in spiritual or decorative crafts.

Geological facts

Known as "Shiva's Eye" in some cultures, it is believed to represent the third eye of Shiva and is considered a talisman for protection and wisdom. In other regions, it is called a "Cat's Eye" shell.

Field identification & locations

Identify by its flat, slightly rounded shape, prominent concentric rings or spiral pattern, and its calcareous (calcium carbonate) composition. It will react to dilute hydrochloric acid. Commonly found washed up on beaches, separating from the snail shell after the animal dies.