Andalusite
Refractive Index |
1.627 to 1.650 |
Birefringence |
0.007 to 0.013 |
Dispersion |
0.016 |
Specific Gravity |
3.05 to 3.21 |
Transparency |
Transparent,Translucent,Opaque |
Pleochroism |
Strong |
Fluorescence |
Weak; green, yellow-green |
Optical Character |
Biaxial - |
Cleavage |
Good |
Fracture |
Uneven |
Lustre |
Vitreous |
Mohs Hardness |
7.5 |