mineral

Pearl

Calcium Carbonate (CaCO3) in the form of Aragonite

Hardness: 2.5–4.5 on Mohs scale; Color: Cream, white, pink, silver; Luster: Pearly (iridescent); Crystal structure: Orthorhombic microcrystalline; Cleavage: None; Specific gravity: 2.60–2.85

Hardness: 2
Color: Cream, white, pink, silver
Luster: Pearly (iridescent)

Identified May 3, 2026More mineral →

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Physical properties

Hardness: 2.5–4.5 on Mohs scale; Color: Cream, white, pink, silver; Luster: Pearly (iridescent); Crystal structure: Orthorhombic microcrystalline; Cleavage: None; Specific gravity: 2.60–2.85

Formation & geological history

Formed biogenically inside the soft tissue (mantle) of a living shelled mollusk. Layers of nacre are deposited around a microscopic irritant over several years.

Uses & applications

Primarily used in jewelry (necklaces, earrings, rings) and as a traditional symbol of wealth and purity. Occasional use in cosmetics and traditional medicine.

Geological facts

Pearls are the only gemstones in the world to be extracted from living animals. Cultured pearls are real pearls grown with human intervention in pearl farms.

Field identification & locations

Identified by their unique luster and the 'tooth test' (natural pearls feel gritty against teeth, while imitations feel smooth). Found in saltwater bays or freshwater lakes/rivers.

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