Tiger's Eye (Rough Specimen)
Pseudomorph of Quartz after Crocidolite · Semi-Precious Gemstone
Crystal System
Trigonal (Quartz); Fibrous habit inherited from crocidolite asbestos fibers
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2 (Quartz) with inclusions of Goethite (FeO(OH)) and Limonite
Formation Process
Metamorphic/Hydrothermal: A pseudomorph formed when quartz replaces the fibrous mineral crocidolite (blue asbestos) while preserving the fibrous structure, followed by iron oxidation.
About This Crystal
Massive, opaque specimen showing earthy to silky luster on fracture surfaces. Displays a characteristic golden-brown to mustard-yellow color with darker chocolate-brown matrix. The texture is distinctly fibrous and granular in the rough state.
Physical Characteristics
Color: Gold, brown, yellow; Streak: Yellow-brown; Cleavage: None; Fracture: Fibrous or splintery; Specific Gravity: 2.64–2.71; Tenacity: Brittle; Fluorescence: Generally inert.
Optical Properties
Refractive Index: 1.544–1.553; Birefringence: 0.009; Displays chatoyancy (cat's eye effect) when polished due to the parallel orientation of internal fibers.
Hardness & Durability
Origin Region
South Africa (Griqaland West), Western Australia, Namibia, and Myanmar. Typically forms in iron formations.
Hardness & Durability
Mohs Hardness: 6.5–7. Excellent durability and toughness for jewelry, though fibrous structure can cause splintering if struck hard.
Care & Maintenance
Clean with warm soapy water and a soft brush. Avoid harsh chemicals and ultrasonic cleaners if the stone has significant surface-reaching fractures.
Rarity & Value
Common; Value is determined by the strength of chatoyancy, richness of color, and lack of dull matrix. Generally inexpensive and widely available.
Special Characteristics
Chatoyancy: The 'eye' effect produced by light reflecting off the internal fibrous structure. This specimen is in its natural, unpolished state where chatoyancy is muted.
Lore & History
Historically worn by Roman soldiers for protection in battle. In modern crystal healing lore, it is traditionaly associated with the Solar Plexus chakra, courage, and grounding energy.