Kyanite

Appearance:

A non-fluorescent, vitreous (pearly) mineral which is translucent to transparent, and can be found in varying shades of blue, white, gray, green, or black.

Other useful information...

Kyanite is formed in metamorphosed peri-aluminous sedimentary rocks.

Physical properties...

Chemistry	Aluminium Silicate (Al2SiO5)
System/Structure	Triclinic (Pinacoidal)
Refractive Index	3.56 - 3.67
Specific Gravity	(not available)
Mohs' Hardness	From 4 to 7