Tiger's Eye (Rough)
Quartz var. Tiger's Eye · Semi-Precious Gemstone / Mineral Specimen
Crystal System
Trigonal (microcrystalline); Habit: Fibrous, massive, and asymmetric slab-like form in this specimen.
Mineral Group
Silicates (Tectosilicate)
Chemical Formula
SiO2 (Silicon Dioxide) with fibrous inclusions of Crocidolite (Iron Silicate) pseudomorphs replaced by Limonite/Goethite
Formation Process
Metamorphic/Hydrothermal. It forms as a pseudomorph, where the fibrous blue mineral Crocidolite is chemically replaced by Silica, while Limonite/Goethite provides the golden-brown color.
About This Crystal
A rough, opaque mineral fragment showing distinct parallel banding. The specimen exhibits a central band of golden-yellow to brown fibrous structure with a silky luster, sandwiched between darker matron-brown to grey host rock with a dull to waxy luster. The surface is uneven with some conchoidal fracturing visible on the darker sections.
Physical Characteristics
Color: Golden-yellow, brown, and grey. Streak: Yellow-brown. Cleavage: None (fibrous structure produces a splintery fracture). Specific Gravity: 2.64-2.71. Tenacity: Brittle. Non-fluorescent.
Optical Properties
Displays chatoyancy (cat's eye effect) due to the parallel alignment of fibrous inclusions. Refractive Index: 1.544-1.553. Birefringence: Weak (0.009). Doubly refractive.
Hardness & Durability
Origin Region
South Africa (Griequaland West), Western Australia, Namibia, and India. Typically found in iron-rich metamorphic rocks.
Hardness & Durability
Mohs Hardness: 6.5 - 7. High durability, though the fibrous nature can make it susceptible to chemicals if not polished. Toughness is generally good.
Care & Maintenance
Clean with warm soapy water and a soft brush. Avoid harsh chemicals (acids) and ultrasonic cleaners which may penetrate the fibers of rough specimens. Store separately to prevent scratching softer stones.
Rarity & Value
Common. Value is determined by the intensity of 'chatoyant' flash and color saturation. Rough specimens like this are inexpensive but highly valued for lapidary work.
Special Characteristics
Strong chatoyant effect when moved under light; the specimen shows a distinct 'silk' sheen in the central golden band. No UV fluorescence.
Lore & History
Ancient Roman soldiers wore it for protection in battle. Historically associated with the 'all-seeing eye.' In modern crystal healing, it is traditionally believed to enhance courage, willpower, and ground the lower chakras (Root and Solar Plexus).