Mineral - Malachite
Malachite
Chemical Properties
Mineral Class
Carbonates
Toxicity
low
Formula
Cu₂[(OH)₂|CO₃]
Unit Cell
a=9.50 b=11.97 c=3.24 β=98° Z=4
Physical Properties
Hardness
3.5 - 4
Streak
green
Density
Heavy (3,5-6)
Cleavage
Perfect after { 2 01}
Fracture
splintery
Tenacity
Brittle
Optical Properties
Color
green
Birefringence
0.254
Luster
Vitreous,
Silky
Transparency
translucent,
opaque
Pleochroism
Geomineralogical Properties
Crystal System
monoclinic
Point Group
monoclinic-prismatic - 2/m
Space Group
P2 1 /c (14)
Habit
tufty, coarse, felted, massive, acicular, kidney-shaped, prismatic, pyramidal, radial, radial, grape-shaped
Formation
Secondary, through the aqueous oxidation of copper-bearing sulfides in the oxidation zone of supergene ore deposits in the presence of carbonate-bearing solutions or rocks.
Paragenesis
Twinning
Arrow-like contact twins after {100}
Rarity
Common
Synonyms
Malachite
Composition
Elements
Mass
CO₂
20.04
CuO
72.03
H₂O
8.09
Italy (Palache et al. 1952)
Groups and Members
Malachite-Rosasite-Group