mineral

Pearl

Aragonite / Calcium Carbonate (CaCO3)

AI-generated identification · may be incorrect

Hardness: 2.5-4.5 (Mohs); Color: White, cream, pink, silver; Luster: Pearly/Iridescent; Crystal Structure: Orthorhombic; Specific Gravity: 2.60-2.85

Hardness: 2
Color: White, cream, pink, silver
Luster: Pearly/Iridescent

Identified May 13, 2026More mineral →

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Physical properties

Hardness: 2.5-4.5 (Mohs); Color: White, cream, pink, silver; Luster: Pearly/Iridescent; Crystal Structure: Orthorhombic; Specific Gravity: 2.60-2.85

Formation & geological history

Organically formed inside the soft tissue of a living shelled mollusk as a defense mechanism against irritants. Composed of concentric layers of nacre.

Uses & applications

Primarily used in jewelry (necklaces, earrings, bracelets) and as an ornamental gemstone. Historically used in medicine and cosmetics.

Geological facts

Pearls are the only gemstones in the world to come from a living creature. They do not require cutting or polishing to reveal their natural beauty.

Field identification & locations

Identify by the 'tooth test' (feeling a slightly gritty texture when rubbed against the edge of a tooth). Found in saltwater oysters and freshwater mussels worldwide.