Tiger's Eye (Unfinished)
Pseudomorph of Quartz after Crocidolite · Semi-Precious Gemstone / Decorative Stone
Crystal System
Trigonal (Hexagonal) system; typically exhibits a massive, fibrous, or platy habit due to the replacement of asbestos fibers.
Mineral Group
Silicates (Tectosilicates)
Chemical Formula
SiO2 (with inclusions of hydrous iron oxide, mainly Goethite FeO(OH))
Formation Process
Metamorphic/Hydrothermal: Formed when parallel veins of crocidolite (blue asbestos) are replaced by silica and subsequently oxidized, turning the blue fibers golden brown.
About This Crystal
The specimen shows an unpolished or weathered surface featuring earthy brown and reddish-orange iron oxidation. When cut, it reveals a golden to reddish-brown coloration with a silky luster and varying degrees of transparency from translucent to opaque.
Physical Characteristics
Color: Gold, brown, and red. Streak: Yellow-brown. Cleavage: None. Fracture: Conchoidal or splintery. Specific Gravity: 2.64–2.71. Fluorescence: Generally inert under UV light.
Optical Properties
Displays chatoyancy (cat's eye effect) caused by the parallel arrangement of acicular inclusions; Refractive Index: 1.544–1.553; Uniaxial positive.
Hardness & Durability
Origin Region
Griqualand West and the Kuruman hills in South Africa; also found in Western Australia and Myanmar.
Hardness & Durability
Mohs Hardness: 6.5 – 7.0; High toughness and good stability for jewelry, though sensitive to strong acids.
Care & Maintenance
Clean with warm soapy water and a soft brush; avoid ultrasonic cleaners and harsh chemicals. Store separately from harder gemstones like diamonds to prevent scratching.
Rarity & Value
Common; Value is determined by the distinctness of the chatoyant 'eye,' color saturation, and lack of dull matrix. Generally inexpensive.
Special Characteristics
Strong chatoyancy when polished; periodic banding of gold and brown; potential for 'Hawk's Eye' (blue) if the iron has not fully oxidized.
Lore & History
Historically used by Roman soldiers for protection in battle. Metaphysically associated with the Solar Plexus chakra, representing courage, willpower, and grounding energy.