Template:Andalusite
From The Gemology Project
Andalusite | |
---|---|
Chemical composition | Al2SiO5 |
Crystal system | orthorhombic |
Hardness | 7.5 |
Optic nature | biaxial - |
Refaction index | 1.63-1.64 |
Birefringence | 0.010 |
Dispersion | low, 0.016 |
Specific gravity | 3.18 |
Lustre | vitreous |
Pleochroism | very strong |