Mineral - Chrysocolla
Chrysocolla
Chemical Properties
Mineral Class
Silicates
Toxicity
none
Formula
(Cu,Al)₂H₂Si₂O₅(OH)₄ · nH₂O
Unit Cell
a=5.72 b=17.70 c=8.00
Physical Properties
Hardness
2 - 4
Streak
whitegreengreen white
Density
Light (<2)
Cleavage
Fracture
conchoidal,
uneven
Tenacity
Brittle
Optical Properties
Color
greenblueturquoise
Birefringence
Luster
Vitreous,
Greasy
Transparency
translucent,
opaque
Pleochroism
Geomineralogical Properties
Crystal System
orthorhombic , amorphous
Point Group
Space Group
Habit
massive, kidney-shaped, stalactitic, grape-shaped
Formation
In the oxidation zone of copper deposits, due to interaction with silicate solutions
Paragenesis
Twinning
Rarity
Common
Synonyms
Chrysocolla
Composition
Elements
Mass
SiO₂
35.80
Al₂O₃
2.00
Fe₂O₃
0.01
CuO
42.00
MgO
0.08
CaO
1.04
Na₂O
0.04
K₂O
0.05
H₂O
19.46
Russia (Dana 1895)