Tanzanite
ID: 114
Tanzanite
Chemical Formula
Ca2Al3(SiO4)3(OH)
Hardness (Mohs)
6-7
Crystal System
Orthorhombic
Streak
White
Luster
Vitreous
Diaphaneity
Transparent
Color
Blue, violet-blue, purplish-blue
Crystal Habit / Mode of Occurrence
Prismatic, typically striated crystals; massive
Fun Facts
Tanzanite is pleochroic, meaning it can display different colors when viewed from different angles.