Pearl
Organic Gemstone - Natural/Cultured Pearl (Calcium Carbonate in the form of Aragonite and Conchiolin) · Organic Gem
Crystal System
Orthorhombic (microcrystalline aragonite platelets)
Mineral Group
Carbonates (Biogenic mineral aggregate)
Chemical Formula
CaCO3 (Aragonite) and organic matrix (Conchiolin)
Formation Process
Biogenic/Biomineralization (produced within the soft tissue of living shelled mollusks as a defense mechanism against irritants)
About This Crystal
A strand of spherical to near-spherical off-white to cream-colored pearls showing a characteristic pearly or silky luster with subtle orient. The pearls are individually knotted on a silk thread and fitted with a metal clasp.
Physical Characteristics
Color ranges from white, cream, silver, to golden with various overtones; streak is white; no cleavage; fracture is uneven; specific gravity is approximately 2.65 to 2.78; tenacity is tough due to interlocking aragonite platelets.
Optical Properties
Refractive index ranges from 1.530 to 1.685 (birefringence obscured by structure); displays orient (iridescence caused by light interference from overlapping micro-layers) and luster.
Hardness & Durability
Origin Region
Saltwater and freshwater environments globally; major producers include Japan, China, Australia, French Polynesia, and the Persian Gulf.
Hardness & Durability
Mohs hardness of 2.5 to 4.5; low toughness against acids and scratching; requires careful wear and maintenance as it is a soft organic gemstone.
Care & Maintenance
Clean with a soft, damp cloth using mild soapy water; never use ultrasonic or steam cleaners, harsh chemicals, or abrasive substances; store separately away from hard gemstones and cosmetics, perfumes, or hairsprays.
Rarity & Value
Varies significantly from common (mass-produced cultured freshwater pearls) to extremely rare (high-grade natural saltwater pearls); value depends on size, shape, luster, surface flawlessness, color, and matching.
Special Characteristics
Displays orient and iridescence (lustrous play of light from micro-layers of aragonite); organic origin produced by mollusks.
Lore & History
Historically associated with purity, wisdom, and wealth across ancient civilizations including Rome, Egypt, and China; traditionally used in crystal healing to promote emotional balance, calmness, and sincerity, though these are cultural beliefs rather than scientific claims.