metamorphic
Tiger's Eye
Pseudomorph of quartz after crocidolite (SiO2)
Hardness: 7 Mohs; Color: Golden-brown to reddish-brown; Luster: Silky; Crystal structure: Trigonal/Fibrous; Specific Gravity: 2.64-2.71; Chatoyancy (shimmering effect).
- Hardness
- 7 Mohs
- Color
- Golden-brown to reddish-brown
- Luster
- Silky
Identified More metamorphic →
Explore Tiger's Eye in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 7 Mohs; Color: Golden-brown to reddish-brown; Luster: Silky; Crystal structure: Trigonal/Fibrous; Specific Gravity: 2.64-2.71; Chatoyancy (shimmering effect).
Formation & geological history
Formed when quartz replaces fibrous crocidolite (blue asbestos) via pseudomorphism, preserving the original fibrous structure. Found in iron formations and metamorphic belts.
Uses & applications
Primarily used in jewelry (cabochons, beads), decorative carvings, and as a popular collector's gemstone due to its chatoyant properties.
Geological facts
The shimmering 'eye' effect shifts as you rotate the stone. While it starts as blue crocidolite (Hawk's Eye), oxidation of iron within the fibers turns it the golden brown characteristic of Tiger's Eye.
Field identification & locations
Look for distinct parallel golden-yellow and brown bands with a silky sheen. It is most commonly found in South Africa and Western Australia.
More like this
