Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron inclusions)

Rock Type: metamorphic

Tiger's Eye

Physical Properties

Hardness: 6.5-7 Mohs; Color: Golden yellow to brown with chatoyancy; Luster: Silky; Crystal structure: Trigonal/Hexagonal (fibrous aggregate); Cleavage: None; Specific Gravity: 2.64-2.71

Formation & Geological History

Formed through the pseudomorphic replacement of crocidolite asbestos fibers by chalcedony/quartz, where the iron in the crocidolite oxidizes to create the yellow-brown color. Most deposits are Proterozoic in age.

Uses & Applications

Primarily used as a gemstone for jewelry (cabochons, beads), decorative carvings, and as a popular specimen for mineral collectors due to its unique optical properties.

Geological Facts

Tiger's eye displays a phenomenon called chatoyancy (the cat-eye effect) caused by the reflection of light off the parallel mineral fibers within the stone. Blue variations are known as Hawk's Eye.

Field Identification & Locations

Identify in the field by its distinct golden-brown banding and silky chatoyance when rotated under light. Major locations include South Africa (Northern Cape), Australia, India, and Namibia.

Identified on: 5/3/2026

Mode: Standard