Class : Sulfides and sulfosalts
    Subclass : Sulfosalts
    Crystal system : Orthorhombic
    Chemistry : Ag₅SbS₄
    Rarity : Uncommon

Stephanite is a late primary sulfide from silver and auro-silver hydrothermal deposits. It is common in most major silver mining districts (gold-silver, lead-zinc-silver, nickel-cobalt-silver veins, etc...). Depending on the type of vein, it is accompanied by different sulfides (sphalerite, galena, tetrahedrite, etc...), but constantly retains a procession of other silver sulfides and sulfosalts with which it is mixed (polybasite, pearceite, acanthite, etc...). It was named in honour of Archduke Victor Stephan, Director of Mines of Austria. Stephanite has a metallic luster and an iron-black colour ; it constitutes tabular to prismatic crystals according to [001], pseudohexagonal, with striated faces parallel to the axis of elongation. Stephanite constitutes a silver ore generally accessory but essential in certain mines

Main photo : Stephanite from St. Andreasberg, Germany © Heritage Auctions

Twinning is known on {110}; less common on {130}, {100} and {010}.

No fakes listed for this mineral species.