Vivianite
Fe3(PO4)2*8H2O
Crystal symmetry |
Monoclinic 2/m |
Unit cell |
a = 10.086 Å |
Identification |
|
Color |
pale green |
Cleavage |
Perfect on {010} |
Mohs scale hardness |
1.5 - 2 |
Diaphaneity |
Transparent to translucent |
Specific gravity |
2.68 g/m3 |
Optical properties |
Biaxial (+) |
Refractive index |
nα = 1.579 - 1.616 |
Birefringence |
δ = 0.050 - 0.059 |
Pleochroism |
Visible; |
2V angle |
Measured: 63° to 83.5° |
Dispersion |
r<v, weak |