Kyanite crystal structure
triclinic

Kyanite

Al2SiO5

Quick Facts

Hardness
4.0
Specific Gravity
3.53
Refractive Index
1.716

Crystal Structure

triclinic[-1]:{100}@1.0 + {010}@0.4 + {001}@1.5 + {110}@0.6
triclinic
-1
{100} {010} {001} {110}

Physical Properties

Crystal Systemtriclinic
Hardness (Mohs)4.0
Specific Gravity3.53
CleavagePerfect {100}, good {010}
FractureSplintery
LustreVitreous to pearly

Optical Properties

Refractive Index1.716
Birefringence0.012-0.017
PleochroismModerate dichroic (colorless, dark blue, violet-blue in blue material)
Dispersion0.02

Interactive Preview

Open this crystal in the CDL Playground to rotate, export, and explore in 3D.

Open in Playground
triclinic[-1]:{100}@1.0 + {010}@0.4 + {001}@1.5 + {110}@0.6