Mineral - Pyrargyrite
Pyrargyrite
Chemical Properties
Mineral Class
Sulfides and sulfosalts
Toxicity
none
Formula
Ag₃SbS₃
Unit Cell
a=11.05 c=8.72 Z=6
Physical Properties
Hardness
2.5
Streak
red
Density
Heavy (3,5-6)
Cleavage
Distinct after {1011}, imperfect after {01 1 2}
Fracture
conchoidal,
uneven
Tenacity
Brittle
Optical Properties
Color
blackred
Birefringence
0.203
Luster
Adamantine
Transparency
translucent,
transparent,
opaque
Pleochroism
Geomineralogical Properties
Crystal System
trigonal
Point Group
ditrigonal-pyramidal - 3m
Space Group
R3c (161)
Habit
prismatic, pyramidal, Rhombohedron, tabular
Formation
(1) Primary hydrothermal as late-magmatic precipitation in low- to medium-temperature veins.
(2) Secondary supergene through enrichment in the oxidation and cementation zones of silver deposits under the influence of antimony-bearing solutions
Paragenesis
Twinning
Rarity
Rarely
Synonyms
Pyrargyrite
Composition
Elements
Mass
Ag
59.82
Sb
22.00
As
0.08
S
17.82
Romania (Palache et al. 1952)
Groups and Members
Proustite-Group