Mineral - Argyrodite
Argyrodite
Chemical Properties
Mineral Class
Sulfides and sulfosalts
Toxicity
low
Formula
Ag₈GeS₆
Unit Cell
a=15.15 b=7.48 c=10.59 Z=4
Physical Properties
Hardness
2.5 - 3
Streak
blackgraygray black
Density
Very Heavy (>6)
Cleavage
Fracture
conchoidal,
uneven
Tenacity
Brittle
Optical Properties
Color
gray
Birefringence
Luster
Metallic
Transparency
opaque
Pleochroism
Geomineralogical Properties
Crystal System
orthorhombic
Point Group
orthorhombic-pyramidal - mm2
Space Group
Pna2 1 (33)
Habit
coarse, dodecahedron, bulbous, granular, spherical, massive, Octahedron, tabular, Triacis octahedron
Formation
In hydrothermal ore deposits
Paragenesis
Twinning
Penetration twins after the spinel law {111}
Rarity
Very rare
Synonyms
Argyrodite
Composition
Elements
Mass
Ag
74.20
Fe
0.68
Ge
4.99
Sn
3.36
Sb
0.01
S
16.45
Bolivia (Berry & Thompson 1962)
Groups and Members
Argyrodite-Group
Name and first discovery : Named after the Greek word "argyrodes" for "silver-bearing," due to its high silver content. First described in 1886
Synonyms : Basitom luster, donacargyrite, plusin luster, reed glass ore
Varieties :
Abbreviation : Agy
literature
Berry, L.G., & Thompson, R.M. (1962). X-ray powder data for ore minerals: the Peacock atlas (Vol. 85). Geological Society of America.