mineral

Pearl

Biogenic CaCO3 (Aragonite)

Hardness: 2.5-4.5 Mohs scale; Color: Creamy white with iridescent orient; Luster: Pearly; Composition: Aragonite (calcium carbonate) and conchiolin.

Hardness: 2
Color: Creamy white with iridescent orient
Luster: Pearly

Identified May 7, 2026More mineral →

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Physical properties

Hardness: 2.5-4.5 Mohs scale; Color: Creamy white with iridescent orient; Luster: Pearly; Composition: Aragonite (calcium carbonate) and conchiolin.

Formation & geological history

Biogenic formation within the soft tissue of a living shelled mollusk. Layers of nacre are deposited around an irritant over several years.

Uses & applications

Primarily used in high-end jewelry (necklaces, earrings) and luxury decorative arts.

Geological facts

The pearl is the only gemstone created by a living animal. Natural pearls are extremely rare, with most modern pearls being 'cultured' or farmed.

Field identification & locations

Identified by its unique pearly luster and smooth (or slightly gritty when rubbed on teeth) texture. Found worldwide in marine and freshwater mollusk habitats.

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