Tiger's Eye
Quartz var. Tiger's Eye · Semi-Precious Gemstone / Decorative Stone
Crystal System
Trigonal (pseudomorph after monoclinic crocidolite); typically found in massive, fibrous, or platy habits rather than distinct crystals.
Mineral Group
Silicates (Tectosilicates subclass, Quartz group)
Chemical Formula
SiO2 (Silicon Dioxide) with fibrous inclusions of Crocidolite (altered to Limonite or Goethite)
Formation Process
Metamorphic/Hydrothermal process through pseudomorphism, where silica replaces fibrous blue asbestos (crocidolite) while maintaining its fibrous structure, followed by oxidation of iron to produce gold/brown tones.
About This Crystal
An opaque, fibrous quartz variety exhibiting a distinct silky luster and chatoyancy. It features alternating bands of golden yellow, honey brown, and dark chocolate black. In this specimen, it is carved into a polished heart shape with smooth, reflective surfaces.
Physical Characteristics
Color: Gold-brown to yellow-brown with black bands; Streak: Yellow-brown or white; Cleavage: None (fibrous structure produces parting); Fracture: Conchoidal to splintery; Specific Gravity: 2.64–2.71; Fluorescence: Generally inert.
Optical Properties
Refractive Index: 1.544–1.553; Birefringence: 0.009; Optical Phenomenon: Strong chatoyancy (cat's eye effect) caused by the fibrous structure; Lustre: Silky when polished; Singly refractive (aggregate).
Hardness & Durability
Origin Region
Primarily the Northern Cape Province of South Africa; also found in Western Australia, India, Burma, and Namibia.
Hardness & Durability
Mohs Hardness: 6.5–7; Toughness: Good (due to fibrous structure); Wearability: Excellent for jewelry including rings and pendants, though it can be scratched by harder stones like topaz or sapphire.
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid ultrasonic cleaners which may damage fibrous layers. Store separately from harder gemstones to prevent scratching. Stable in sunlight and most household chemicals.
Rarity & Value
Common; Value is determined by the intensity of the chatoyant 'shimmer' and the evenness of banding. Treatments: Often dyed or heat-treated (to produce Red Tiger's Eye). Unheated golden-brown material is abundant and affordable.
Special Characteristics
Displays prominent chatoyancy, where a band of light moves across the surface as the stone is rotated, mimicking the eye of a tiger. This effect is most visible in cabochons and polished shapes like this heart.
Lore & History
Historically worn as a protective amulet by Roman soldiers to grant courage and protection in battle. In metaphysical lore, it is associated with the Solar Plexus chakra and believed to promote mental clarity, grounding, and personal power.