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Tiger's Eye

Last updated: April 2026

Chatoyant quartz formed by pseudomorphous replacement of crocidolite asbestos fibers with silica. Golden-yellow Tiger's Eye results from iron oxide staining of the silica pseudomorph. Hawk's Eye is the blue-grey unaltered variety. Red Tiger's Eye (ox-blood) is heat-treated. Always cut en cabochon to display chatoyancy.

Tiger's Eye has a specific gravity of 2.65 and a refractive index of 1.544–1.553, with a Mohs hardness of 7. It is aggregate.

Physical & Optical Properties

RI Range1.544–1.553
SG Range2.64–2.71
SG Typical2.65
Hardness (Mohs)7
Crystal SystemTrigonal
Optic CharacterAggregate
Dispersion0.013
Fluorescence LWInert
Fluorescence SWInert
Chelsea FilterInert
PleochroismNone
ColorsYellow Orange, Brown
SpeciesQuartz
Yellow OrangeBrown

AgateAmethystAmetrineAventurineBloodstoneCarnelianChalcedonyChrysopraseCitrineHawk's EyeOnyxPrasioliteRock CrystalRose QuartzSmoky Quartz

Key Differentiators

Treatments

Price Context

Natural — low ($/ct)$1
Natural — high ($/ct)$20
NotePer carat; common commercial gem; South African origin dominant; value driven by quality of chatoyancy and color intensity

Price context is approximate. GemID is not an appraisal tool. Results are indicators, not certified valuations.

Measurement Guides

How to Identify a GemstoneHow to Measure Specific GravityHow to Use a RefractometerUV Fluorescence Testing

Identifying a tiger's eye? GemID walks through these tests in order — RI, SG, fluorescence, and more.

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Studying for the GIA, FGA, or FEEG practical? Tiger's Eye is one of the 130 species in GemID’s drill and exam pool — practice identifying it from its measured properties under timed exam conditions.

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