Tiger's Eye

Hardness: 6.5-7 on the Mohs scale. Color: Golden to reddish-brown with a silky luster due to the fibrous structure. Luster: Silky to vitreous. Crystal Structure: Trigonal (as a variety of quartz). Cleavage: None. Specific Gravity: 2.64-2.71. It exhibits chatoyancy, a moving optical effect created by the reflection of light from parallel fibrous inclusions.

Tiger's Eye forms when quartz slowly replaces fibrous crocidolite (blue asbestos) within rock pockets. Over time, the iron in the crocidolite oxidizes, turning the blue crocidolite fibers golden or reddish-brown. This silicification process occurs in metamorphic environments, often at relatively low temperatures and pressures. Its geological age varies depending on the specific deposit, but it is typically found in Precambrian to Cenozoic rocks.

Predominantly used as a popular gemstone for jewelry, including rings, pendants, beads, and cabochons. It is also used for ornamental carvings, decorative objects, and as a material for lapidary arts. Due to its striking appearance and perceived metaphysical properties, it is also popular in crystal healing and collection.

Tiger's Eye is a pseudomorph of quartz, meaning it formed as one mineral (crocidolite, a type of asbestos) and was later replaced by another (quartz) while retaining the original fibrous structure. This is what creates its characteristic chatoyancy. It has been used as a protective stone throughout history and is often associated with courage and confidence.

In the field, Tiger's Eye is easily identified by its distinctive chatoyancy (the 'cat's eye' effect) and its golden to reddish-brown color with parallel bands of light and dark. It commonly occurs in metamorphic rocks. Major deposits are found in South Africa (world's largest), Australia, Brazil, India, Myanmar (Burma), Namibia, and the USA (Arizona). For collectors, look for strong chatoyancy, rich color, and minimal inclusions or fractures. Polished specimens best display its unique optical properties.