mineral
Likely rough blue-gray kyanite
Kyanite, Al₂SiO₅
AI-generated identification · may be incorrectBlue-gray, vitreous to pearly, with elongated/bladed crystals and distinct cleavage; Mohs hardness varies by direction (about 4.5–5 parallel to the blades and 6.5–7 across them). The small, partly obscured specimen makes identification uncertain.
Identified More mineral →
Explore Likely rough blue-gray kyanite in the encyclopedia →Identify your own rocks.
Get a report just like this from any photo, free.
Physical properties
Blue-gray, vitreous to pearly, with elongated/bladed crystals and distinct cleavage; Mohs hardness varies by direction (about 4.5–5 parallel to the blades and 6.5–7 across them). The small, partly obscured specimen makes identification uncertain.
Formation & geological history
Forms during high-pressure regional metamorphism of aluminum-rich sediments, commonly in schist and gneiss; age depends on its host rock and cannot be determined from the image.
Uses & applications
Used in refractory ceramics and, when clear and attractive, cut as a gemstone or kept as a mineral specimen.
Geological facts
Kyanite, andalusite, and sillimanite share the formula Al₂SiO₅ but form under different temperature-pressure conditions.
Field identification & locations
Look for blue, elongated blades and direction-dependent hardness; common in metamorphic rocks worldwide, including the United States, Brazil, Nepal, and Switzerland.
More like this
Other mineral specimens
Gneiss or Schist
Gneiss or Mica Schist with Garnet
Metamorphic
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
Tumbled granite
Granite, a coarse-grained felsic intrusive igneous rock
igneous
Epidote
Epidote | Ca2(Al2,Fe3+)(SiO4)(Si2O7)O(OH)
metamorphic
Pegmatite with Tourmaline and Quartz
Igneous Pegmatite
igneous
Granite
Granite (Phaneritic intrusive igneous rock)
igneous