Mineral - Brochantite
Brochantite
Chemical Properties
Mineral Class
Sulphates
Toxicity
none
Formula
Cu₄[(OH)₆|(SO₄)]
Unit Cell
a=13.08 b=9.85 c=6.02 β=103° Z=4
Physical Properties
Hardness
3.5 - 4
Streak
green
Density
Very Heavy (>6)
Cleavage
Perfect after {100}
Fracture
uneven
Tenacity
Brittle
Optical Properties
Color
green
Birefringence
0.072
Luster
Vitreous,
Pearly
Transparency
translucent,
transparent
Pleochroism
Geomineralogical Properties
Crystal System
monoclinic
Point Group
monoclinic-prismatic - 2/m
Space Group
P2 1 /c (14)
Habit
crusty, acicular, prismatic
Formation
Oxidation zone of copper deposits
Paragenesis
Twinning
Rarity
Rather rare
Synonyms
Brochantite
Composition
Elements
Mass
SO₃
17.54
CuO
70.29
H₂O
11.96
Chile (Palache et al. 1952)