Tiger's Eye
Quartz var. Tiger's Eye · Semi-Precious Gemstone
Crystal System
Trigonal crystal system; typically occurs in fibrous, massive habit as a pseudomorph.
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2 with inclusions of Crocidolite (asbestos fibers replaced by silica) and Limonite (Fe2O3·nH2O)
Formation Process
Pseudomorphic formation: Originally formed as crocidolite (blue asbestos) via hydrothermal processes, which was then replaced by silica while preserving the fibrous structure.
About This Crystal
An opaque, fibrous quartz displaying a golden-yellow to brown color with a silky luster. When polished into a cabochon or tumbled stone like the specimen shown, it exhibits wavy bands of varying shades.
Physical Characteristics
Color: Golden-brown to black; Streak: White to yellow-brown; Cleavage: None; Fracture: Splintery to conchoidal; Specific Gravity: 2.64–2.71; Luster: Vitreous to silky.
Optical Properties
Displays chatoyancy (cat's eye effect) caused by light reflecting off the parallel fibrous inclusions. Refractive Index: 1.544–1.553; Birefringence: 0.009.
Hardness & Durability
Origin Region
South Africa (Northern Cape), Australia, Myanmar, India, and Namibia. Often found in iron-rich metamorphic formations.
Hardness & Durability
Mohs hardness: 6.5–7. Good toughness and durability, making it suitable for daily wear in rings and bracelets.
Care & Maintenance
Clean with warm soapy water and a soft brush. Avoid harsh chemicals and ultrasonic cleaners if the stone has significant fractures. Store away from harder stones like diamonds.
Rarity & Value
Common; very affordable. Value is determined by the strength of the chatoyancy, evenness of color, and quality of the polish. Red variants are usually heat-treated.
Special Characteristics
Chatoyancy is the primary feature; when the stone is moved, light reflects off the fibers to create a 'moving' band of light similar to a feline eye.
Lore & History
Historically worn by Roman soldiers for protection in battle due to its 'all-seeing' quality. In modern crystal healing, it is associated with the solar plexus chakra and believed to promote courage, focus, and grounding.