Tiger's Eye
Quartz var. Tiger's Eye · Semi-Precious Gemstone
Crystal System
Trigonal, massive or fibrous habit
Mineral Group
Silicates (Tectosilicate subgroup)
Chemical Formula
SiO2 with inclusions of oxidized crocidolite
Formation Process
Pseudomorphic replacement of crocidolite (riebeckite asbestos) by quartz under hydrothermal and weathering conditions
About This Crystal
A polished, rectangular cabochon displaying a rich golden-brown to dark brown body color with fibrous banding and a characteristic silky chatoyancy (cat's eye effect) shifting across the surface under light.
Physical Characteristics
Color: golden-brown, yellow-brown, dark brown; Streak: white; Cleavage: none; Fracture: conchoidal to uneven; Specific Gravity: 2.64-2.71; Tenacity: brittle
Optical Properties
Refractive Index: 1.544-1.553; Birefringence: 0.009; Optically uniaxial positive; Strong chatoyancy due to parallel fibrous structure
Hardness & Durability
Origin Region
South Africa, Western Australia, USA, Canada, Brazil, India
Hardness & Durability
Mohs hardness of 7; tough and durable due to fine quartz intergrowth; suitable for most jewelry types
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid harsh chemicals, ultrasonic cleaners, and prolonged direct sunlight to prevent fading
Rarity & Value
Common; very affordable, with value determined by chatoyancy quality, color depth, and lack of fractures
Special Characteristics
Chatoyancy (cat's-eye effect) caused by the reflection of light from parallel microscopic fibers of altered amphibole minerals
Lore & History
Historically used as a protective talisman by Roman soldiers and ancient cultures against curses and ill-wishes; associated with the Solar Plexus chakra, courage, grounding, and mental clarity in modern crystal lore