mineral

Pearl

Calcium Carbonate (Aragonite/Calcite) with Conchiolin (CaCO3)

Hardness: 2.5-4.5 Mohs scale; Color: white, cream, pink, silver; Luster: Pearly (iridescent); Crystal structure: Orthorhombic; Cleavage: none; Specific gravity: 2.60-2.85

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

Identified June 23, 2026More mineral →

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Physical properties

Hardness: 2.5-4.5 Mohs scale; Color: white, cream, pink, silver; Luster: Pearly (iridescent); Crystal structure: Orthorhombic; Cleavage: none; Specific gravity: 2.60-2.85

Formation & geological history

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

Uses & applications

Primarily used in jewelry (necklaces, earrings, rings) and as a decorative element in high-end fashion and collectibles.

Geological facts

Pearls are the only gemstones in the world to be extracted from a living animal. They are the birthstone for June and have been harvested for over 4,000 years.

Field identification & locations

Identify by the 'tooth test' (real pearls feel gritty against teeth) and checking for surface irregularities. Found in both saltwater and freshwater environments worldwide.

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