Acanthite


Composition: Ag2S
Crystal System : Monoclinic
Colours: Silver-grey, blackish-grey
Lustre : Metallic
Hardness (H) : 2.0-3.5
Specific Gravity (S.G) : 7.2-7.4

Distribution

Rare.  Generally seen only in polished section. Minute "needles" of acanthite on native silver are almost certainly of supergene (or even post-mining) origin.

Occurrence

  • Hypogene
  • Supergene