Mineral - Tennantite-(Zn)
Tennantite-(Zn)
Chemical Properties
Mineral Class
Sulfides and sulfosalts
Toxicity
low
Formula
Cu₆(Cu₄Zn₂)As₄S₁₂S
Unit Cell
a=10.19 Z=2
Physical Properties
Hardness
3 - 4.5
Streak
blackgraygray black
Density
Heavy (3,5-6)
Cleavage
Fracture
conchoidal
Tenacity
Brittle
Optical Properties
Color
blackgray
Birefringence
Luster
Metallic
Transparency
opaque
Pleochroism
Geomineralogical Properties
Crystal System
isometric
Point Group
hextetrahedral - 4 3m
Space Group
I 4 3m (217)
Habit
dodecahedron, Octahedron, pyramidal, Tetrahedron, Triacis octahedron, Cube
Formation
Primary hydrothermal in polymetallic vein deposits or massive sulfide deposits through precipitation from moderately warm (mesothermal to epithermal), copper-rich solutions under reducing conditions.
Paragenesis
Twinning
Contact- and Penetration twins after {111}
Rarity
Rather rare
Synonyms
Tennantite-(Zn)
Composition
Elements
Mass
Cu
35.72
Ag
13.65
Zn
6.90
Pb
0.86
Fe
0.42
As
17.18
Sb
0.13
S
25.04
Colorado (Palache et al. 1952)
Groups and Members
Tetrahedrite-Group
Tennantite-Subgroup