metamorphic

Tiger's Eye

Pseudomorph of Quartz after Crocidolite (SiO2 with iron oxides)

AI-generated identification · may be incorrect

Hardness: 7 (Mohs); Color: Golden-brown to yellow-gold; Luster: Silky; Crystal structure: Trigonal (fibrous); Cleavage: None (fractures); Specific Gravity: 2.64–2.71

Hardness: 7 (Mohs)
Color: Golden-brown to yellow-gold
Luster: Silky

Identified March 11, 2026More metamorphic →

Explore Tiger's Eye in the encyclopedia →

Identify your own rocks.

Get a report just like this from any photo, free.

App Store Google Play

Physical properties

Hardness: 7 (Mohs); Color: Golden-brown to yellow-gold; Luster: Silky; Crystal structure: Trigonal (fibrous); Cleavage: None (fractures); Specific Gravity: 2.64–2.71

Formation & geological history

Formed when quartz replaces the fibrous mineral crocidolite (asbestos) through a process of pseudomorphism, where the original fibrous structure is retained. Found in Precambrian metamorphic rocks, often over 2 billion years old.

Uses & applications

Widely used in jewelry (cabochons, beads), decorative carvings, and as a popular semi-precious stone for collectors due to its unique optical properties.

Geological facts

Exhibits a distinct optical effect known as chatoyancy, where a silky band of light moves across the stone as it is turned. While it begins as hazardous blue asbestos, the quartz replacement makes it safe to handle.

Field identification & locations

Identify in the field by its distinct golden-brown bands and 'cat's-eye' light reflection. Common locations include South Africa (Northern Cape), Western Australia, India, and the USA (California/Arizona).