Tiger's Eye
Quartz var. Tiger's Eye · Semi-Precious Gemstone and Ornamental Stone
Crystal System
Trigonal, massive to microcrystalline aggregate habit
Mineral Group
Silicates (Subgroup: Tectosilicates)
Chemical Formula
SiO2 (Silicon Dioxide with inclusions of altered crocidolite asbestos)
Formation Process
Pseudomorphic replacement process where quartz slowly replaces original fibrous crocidolite (riebeckite) asbestos fibers
About This Crystal
The specimen is a smoothly tumbled, oval-shaped gemstone exhibiting a warm, golden-brown to honey-yellow color palette with deep dark brown bands. It has a high-polished, glass-like to silky luster and displays strong chatoyancy (the characteristic cat's eye band of light shifting across the fibrous surface)
Physical Characteristics
Color ranges from golden yellow, yellow-brown to deep brown with silky chatoyant streaks; streak is white; no true cleavage (fractures instead); fracture is conchoidal to uneven; specific gravity is approximately 2.64 to 2.71; tenacity is brittle
Optical Properties
Uniaxial positive optical character; refractive index ranges from 1.544 to 1.553; birefringence is 0.009; strongly chatoyant due to parallel fibrous structure scattering light; opaque to translucent
Hardness & Durability
Origin Region
South Africa, Western Australia, USA, Brazil, India, and China; typically found in metamorphic formations
Hardness & Durability
Mohs hardness of 7; good toughness and durability making it suitable for daily wear in jewelry like rings, pendants, and bracelets, provided it is securely set
Care & Maintenance
Safe to clean with warm soapy water and a soft brush; avoid harsh chemicals, prolonged exposure to high heat, and harsh ultrasonic cleaners; store away from harder stones to prevent scratching
Rarity & Value
Common and widely available; value is determined by chatoyancy strength, color saturation, and absence of cracks; typically very affordable, ranging from inexpensive tumbled stones to moderately priced high-grade cabochons; generally untreated, though sometimes heat-treated to produce red tiger's eye or acid-treated for lighter colors
Special Characteristics
Pronounced chatoyancy (cat's-eye effect) caused by the reflection of light off parallel fibrous silicate inclusions running through the quartz matrix
Lore & History
Historically used as a protective amulet by ancient Romans and Egyptian soldiers to ward off curses and bring bravery; associated with the Solar Plexus and Sacral chakras; in modern crystal healing, it is traditionally believed to enhance focus, grounding, willpower, and prosperity (noted as traditional lore, not scientific claims)