mineral

Pearl

Biogenic CaCO3 (Aragonite and Calcite)

AI-generated identification · may be incorrect

Hardness: 2.5-4.5 (Mohs scale); Color: Silver-grey, white, cream; Luster: Pearly (iridescent); Crystal structure: Orthorhombic; Specific Gravity: 2.60-2.85

Hardness: 2
Color: Silver-grey, white, cream
Luster: Pearly (iridescent)

Identified May 3, 2026More mineral →

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Physical properties

Hardness: 2.5-4.5 (Mohs scale); Color: Silver-grey, white, cream; Luster: Pearly (iridescent); Crystal structure: Orthorhombic; Specific Gravity: 2.60-2.85

Formation & geological history

Produced within the soft tissue of a living shelled mollusk or other animal; chemically composed of calcium carbonate in minute crystalline form, which has been deposited in concentric layers.

Uses & applications

Primarily used in jewelry such as necklaces, earrings, and rings; also regarded as a collector's gemstone and used in some cosmetic powders.

Geological facts

The 'Pearl of Lao Tzu' is one of the largest pearls ever found. Pearls are the only gemstones made by living creatures.

Field identification & locations

Identify by their unique luster and smooth texture; the 'tooth test' (grittiness against teeth) can differentiate real pearls from glass beads. Found in saltwater or freshwater mollusk habitats.