Mineral - Volborthite
Volborthite
Chemical Properties
Mineral Class
Vanadates
Toxicity
none
Formula
Cu₃(V₂O₇)(OH)₂ · 2H₂O
Unit Cell
a=10,61 b=5,87 c=7,21 β=95° Z=2
Physical Properties
Hardness
3.5
Streak
green
Density
Normal (2-3,5)
Cleavage
Eine, perfekt
Fracture
uneven
Tenacity
Brittle
Optical Properties
Color
yellowgreen
Birefringence
0,023
Luster
Vitreous,
Greasy,
Pearly,
Waxy
Transparency
translucent,
opaque
Pleochroism
Geomineralogical Properties
Crystal System
monoclinic
Point Group
Space Group
Habit
leafy, coarse, crusty, spherical, massive, rosette, tabular
Formation
Sekundär, in der Oxidationszone von Vanadiumlagerstätten
Paragenesis
Twinning
Rarity
Rather rare
Synonyms
Volborthite
Composition
Elements
Mass
V₂O₅
36,7
SiO₂
1,4
V₂O₃
1,7
CuO
48,8
H₂O
11,5
Italien
Groups and Members
Volborthit-Gruppe