metamorphic
Tiger's Eye (Unpolished)
Pseudomorph of Quartz after Crocidolite (SiO2)
Hardness: 6.5-7.0 (Mohs); Color: Golden brown, honey yellow, brownish; Luster: Silky to glassy; Crystal Structure: Trigonal (fibrous texture); Specific Gravity: 2.64-2.71.
- Hardness
- 6
- Color
- Golden brown, honey yellow, brownish
- Luster
- Silky to glassy
Identified More metamorphic →
Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Hardness: 6.5-7.0 (Mohs); Color: Golden brown, honey yellow, brownish; Luster: Silky to glassy; Crystal Structure: Trigonal (fibrous texture); Specific Gravity: 2.64-2.71.
Formation & geological history
Formed when quartz replaces fibrous crocidolite (blue asbestos) via metasomatism, maintaining the parallel fibrous structure. Most deposits are Precambrian in age.
Uses & applications
Predominantly used as a gemstone for jewelry (cabochons), ornamental carvings, and 'metaphysical' healing stones. Also highly valued by mineral collectors.
Geological facts
The shimmering effect seen in the rock is called chatoyancy. While it starts as blue crocidolite, the iron oxidation during the replacement process gives it the characteristic golden-brown color.
Field identification & locations
Identify in the field by its distinct parallel fibrous structure and the 'moving' band of light (chatoyancy) when tilted. Commonly found in South Africa, Western Australia, and Namibia.
More like this
