Mineral - Stannite
Stannite
Chemical Properties
Mineral Class
Sulfides and sulfosalts
Toxicity
low
Formula
Cu₂FeSnS₄
Unit Cell
a=5.44 c=10.73 Z=2
Physical Properties
Hardness
4
Streak
black
Density
Heavy (3,5-6)
Cleavage
Indistinct after {110} and {001}
Fracture
uneven
Tenacity
Brittle
Optical Properties
Color
blackgraybronze
Birefringence
Luster
Metallic
Transparency
opaque
Pleochroism
Geomineralogical Properties
Crystal System
tetragonal
Point Group
tetragonal-scalenohedral - 4 2m
Space Group
I 4 2m (121)
Habit
coarse, dipyramidal, massive, prismatic, pyramidal, Tetrahedron
Formation
(1) Primary magmatic formation in high-temperature, hydrothermal tin-tungsten-quartz veins and in pneumatolytic greisen deposits
(2) In volcanic-exhalative, sulfide deposits (VMS) through hydrothermal precipitation at moderate temperatures.
Paragenesis
Twinning
Penetration twins after {102}
Rarity
Rarely
Synonyms
Stannite
Composition
Elements
Mass
Cu
29.24
Fe
13.95
Zn
0.08
Sn
27.14
S
28.88
Bolivia (Palache et al. 1952)
Groups and Members
Stannite-Group