Kyanite
Chemical Formula	Al2SiO5
Species	Silicates
Crystal System	Triclinic
Mohs Scale	5-7
Specific Gravity	3.53-3.67
Color	Blue, white, rarely green, gray, yellow, pink, orange, and black, can be zoned
Streak	White
Luster	Vitreous, Sub-Vitreous, Greasy, Pearly
Refractive Index	n = 1.712 - 1.718 n = 1.720 - 1.725 n = 1.727 - 1.734
Diaphaneity	Transparent, Translucent
Cleavage	PerfectPerfect on , good on
Fracture	Splintery
Crystal Habit：Columnar; fibrous; bladed
Geological Setting：Metamorphic rocks of moderately high pressure regional metamorphism.