Mineral phase
IMA name
Acanthite
Secondary names
Silver Glance
Class
non-silicate mineral
Compound type
sulfide
Formula
$Ag_2S$
Chemical formula
Ag2S
Elemental formula
Ag2 S
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Ag$ Silver element 2 constituent element main
$S$ Sulfur element 1 constituent element main

Strunz

Class
sulfides - sufosalts (02)
Division
metal sulfides, M:S sup 1:1 (mainly 2:1) (02.B)
Family
with Cu, Ag, Au (02.BA)
Code
02.BA.30a

Dana

Major class
sulfides (II)
Class
sulfides - including selenides and tellurides (02)
Type
where AmBnXp, with (m+n):p=2:1 (02.04)
Group
Acanthite group (02.04.01)
Code
02.04.01.01
Phase type
crystalline
Crystal system
monoclinic
Crystal class
prismatic
Crystal class symbol
2/m (C2h)
Composition order
ordered
Molar mass
247.80 $g/mol$
Density
7.2 - 7.4 $g/cm^3$
State NTP
solid
Refringence type
uniaxial
Pure color
gray
Color
lead gray, black
Diaphaneity
opaque
Luster
metallic