Mineral Species:  Quartz var. Tiger Eye

Chemical Formula: SiO2

Chemical Name: Silicon Dioxide

Mineral Class: Tectosilicate

Mineral Notes: Tiger Eye is a brown variety of Quartz containing highly lustrous yellow and brown parallel fibers. The yellow-gold colours are due to iron oxides, although the same effect is sometimes obtained from inclusions of Rutile. Because of the property of chatoyancy, it is very popular as a gem stone.

Description: This specimen is an elongated, polished slice of Tiger Eye with outstandingly good chatoyancy of the various coloured bands. The effect is especially strong in the irregular gold-coloured zones. Close inspection shows these to be composed of very thin parallel fibres, which reflect and scatter light to produce the remarkable effect.

Location: Marra Mamba, Western Australia, Australia.