Proustite

Proustite-Pyrargyrite Series. The As analogue of pyrargyrite. Trigonal dimorph of Xanthoconite. One of the so-called "ruby silvers".

History

Activities related to discovery and approval of the group members

Structural context

Proustite
Crystal System trigonalCrystal Class hexagonal scalenohedralSpace Group R-3c
a6.88—10.8418 (10.137)
b6.88—10.8418 (10.137)
c6.88—8.72 (8.3962)
alpha90—103.42 (92.2367)
beta90—103.42 (92.2367)
gamma103.42—120 (117.2367)
volume293.7—887.667 (779.6903)

Based on 6 measurements

Chemical context

Stoichiometric formulas

Proustite
mindat.org
  • March 13, 2023Ag3AsS3
IMA
  • March 13, 2023Ag3AsS3
mineralogy.rocks
  • Aug. 30, 2022Ag3As3+S2-3

Elements recorded on EPMA

6
Ag
6
As
6
S

Physical properties

ColorColor entities, recognized using a custom trained NER model
  • scarlet
  • vermilion
  • reddish gray
Color noteOriginal color note from the source
Scarlet, vermilion or reddish gray
StreakStreak entities, recognized using a custom trained NER model
  • vermilion red
Streak noteOriginal streak note from the source
Vermilion red
Lustre
Adamantine
Fracture
Irregular/Uneven
Conchoidal
Luminescence
None
Tenacity
brittle
Hardness
2—2.5
Calculated density
5.625