Mineral - Liroconite
Liroconite
Chemical Properties
Mineral Class
Arsenates
Toxicity
low
Formula
Cu₂Al[(OH)₄|AsO₄] · 4H₂O
Unit Cell
a=12.66 b=7.56 c=9.91 β=91° Z=4
Physical Properties
Hardness
2 - 2.5
Streak
blue
Density
Normal (2-3,5)
Cleavage
Indistinct after {110} and {011}
Fracture
conchoidal,
uneven
Tenacity
Brittle
Optical Properties
Color
greenblue
Birefringence
0.063
Luster
Vitreous,
Resinous
Transparency
translucent,
transparent
Pleochroism
Geomineralogical Properties
Crystal System
monoclinic
Point Group
monoclinic-prismatic - 2/m
Space Group
C2/c (15)
Habit
dipyramidal, lenticular
Formation
Secondary, through aqueous oxidation of arsenides and copper-bearing sulfides (such as chalcopyrite or tennantite) in the oxidation zone of supergene copper deposits.
Paragenesis
Twinning
Contact twins after {100}
Rarity
Rare
Synonyms
Liroconite
Composition
Elements
Mass
P₂O₅
3.73
As₂O₅
23.05
Al₂O₃
10.85
Fe₂O₃
0.98
CuO
36.38
H₂O
25.01
England (Palache et al. 1952)