Iolite

Color:Blue, Violet, Brownish 
Color of streak: White
Mohs' hardness: 7-71/2 
Density: 2.58-2.66
Cleavage: Good
Fracture: Conchoidal, Uneven, brittle
Transparency: Transparent translucent 

 

 

The color of iolite (Greek, Violet ) is usually blue. Inclusions of hematite and goethite sometimes cause reddish sheen or aventurescence. It has a greasy vitreous luster. Deposits  found in Myanmar, Brazil, India, Madagascar, Sri Lanka, and the United States.