mineral
Kyanite
Kyanite (Al2SiO5)
AI-generated identification · may be incorrectHardness varies significantly depending on the direction: 4.5 to 5 parallel to the length, and 6.5 to 7 across the blade. Typically blue, but can be white, gray, green, or black. Vitreous to pearly luster. Triclinic crystal system, usually forming distinct bladed crystals.
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Physical properties
Hardness varies significantly depending on the direction: 4.5 to 5 parallel to the length, and 6.5 to 7 across the blade. Typically blue, but can be white, gray, green, or black. Vitreous to pearly luster. Triclinic crystal system, usually forming distinct bladed crystals.
Formation & geological history
Forms primarily in aluminum-rich metamorphic pegmatites and gneiss resulting from the dynamic metamorphism of argillaceous sediments under high pressure.
Uses & applications
Used in the manufacture of refractory products, ceramics, porcelain plumbing fixtures, and occasionally as a gemstone in jewelry.
Geological facts
Kyanite is one of the best examples of anisotropy in minerals, having distinctly different physical hardnesses depending on which direction you scratch it.
Field identification & locations
Easily identified by its characteristic bladed crystal habit, distinct blue coloration, and extreme hardness anisotropy. Found worldwide, notably in Switzerland, Brazil, USA, and Nepal.
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Other mineral specimens
Gneiss or Schist
Gneiss or Mica Schist with Garnet
Metamorphic
Sandstone (with potential mineral staining/concretions)
Arenite (SiO2 based)
sedimentary
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
Septarian Pebble
Septarian nodule / Concretion
sedimentary