Al2SiO5Triclinic
Kyanite
Al2SiO5
SilicatesChemical FormulaAl2SiO5
Crystal SystemTriclinic
Mohs Hardness7 (varies)
Specific Gravity3.68
ColorBlue, white, gray, green
LusterVitreous to pearly
StreakColorless to white
CleavageOne direction
FractureSplintery
Occurrence
Found in metamorphic rocks. Distinctive blue blade crystals. Hardness varies by direction.