$Eagle\'s Eye (Grey Tiger\'s Eye) (Pseudomorph of Quartz after Crocidolite (SiO2)) — mineral$

mineral

Eagle\'s Eye (Grey Tiger\'s Eye)

Pseudomorph of Quartz after Crocidolite (SiO2)

AI-generated identification · may be incorrect

Hardness: 6.5-7 Mohs; Color: Grey, blue-grey, silver; Luster: Silky; Structure: Hexagonal (trigonal); Cleavage: None; Chatoyancy (cat\'s eye effect).

Hardness: 6
Color: Grey, blue-grey, silver
Luster: Silky

Identified July 15, 2026More mineral →

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Physical properties

Hardness: 6.5-7 Mohs; Color: Grey, blue-grey, silver; Luster: Silky; Structure: Hexagonal (trigonal); Cleavage: None; Chatoyancy (cat\'s eye effect).

Formation & geological history

Formed through the pseudomorphism of crocidolite (asbestos) by silica. It is a variation of hawk\'s eye where the iron has not oxidized to the golden-brown of tiger\'s eye.

Uses & applications

Primarily used for ornamental carvings, jewelry (cabochons, beads), and as a collector specimen due to its unique optical properties.

Geological facts

It is a member of the chalcedony family. Unlike traditional golden tiger\'s eye, eagle\'s eye maintains a cooler, greyish-blue palette because the original iron content remains in a lower oxidation state.

Field identification & locations

Identify by its distinct silky luster and chatoyant bands that move as the stone is rotated under light. Commonly found in South Africa and Western Australia.