Copper Hydroxy Carbonate
Cu3(CO3)2(OH)2
Chemical name
Copper Hydroxy Carbonate |
Mineral name
Azurite |
Chemical formula
Cu3(CO3)2(OH)2 |
Crystal system
monoclinic |
Crystal Class
monoclinic-prismatic (2/m) |
Space Group
P2_1/c |
Unit cell
a [Å]:5.01 b [Å]:5.85 c [Å]:10.35 |
Molecular weight [g/mol]
344,65 |
Formula units
Z=2 |
Twinning
rare on {-101}, {-102}, {001} |
Mohs hardness
3.5 - 4 |
Density [g/cm3]
3.77 |
Cleavage
nearly perfect on {011}, distinct on {100}, indistinct on {110} |
Fracture / Tenacity
conchoidal |
Color
(azure-)blue, very dark to pale blue, pale blue in transmitted light |
Streak
light blue |
Transparency
transparent to translucent |
Luster
vitreous |
Optical character
biaxial (+) |
Refractive Index
nα=1.730; nβ=1.758; nΥ=1.838 |
Birefringence δ
0.108 |
Pleochroism δ
moderate to strong |
Piezoelectric crystals |
T(c) [°C]
nε = 1.568–1.602 |