gemstone

Blue Tiger's Eye (Hawk's Eye)

Pseudomorph of Quartz after Crocidolite (SiO2)

Hardness 7 on Mohs scale, dark blue to bluish-gray color, vitreous to silky luster, trigonal crystal structure (microcrystalline quartz), no cleavage, specific gravity around 2.64-2.71. Displays distinct chatoyancy (cat's-eye effect).

Identified July 26, 2026More gemstone →

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Physical properties

Formation & geological history

Formed through pseudomorphism where quartz replaces fibrous crocidolite (blue asbestos) crystals while preserving their fibrous structure. The blue color is due to unoxidized iron within the original crocidolite fibers.

Uses & applications

Used widely as a gemstone in jewelry making, beadwork, cabochons, carvings, and ornamental objects. Highly favored in lapidary arts.

Geological facts

Also known as Hawk's Eye or Falcon's Eye. Unlike golden tiger's eye, where iron has oxidized into limonite giving a golden yellow color, blue tiger's eye retains its original blue iron content.

Field identification & locations

Identified by its deep indigo/navy blue silky sheen and chatoyant band when rotated under light. Major source locations include South Africa, Australia, Brazil, India, and Namibia.

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