Argentopyrite

minerals

Formula: AgFe2S3
Sulphide, paramorph of sternbergite
Specific gravity: 4.25
Hardness: 3½ to 4
Streak: Grey
Colour: Bronze-brown, tarnishing to lead-grey
Environments

Hydrothermal environments

Argentopyrite is a rare sulphide in silver-bearing hydrothermal veins, associated with arsenic, proustite, pyrargyrite, pyrostilpnite, xanthoconite, sternbergite, stephanite, pyrite, nickelskutterudite, dolomite, calcite and quartz (HOM).

Localities

The type locality is Jáchymov, Karlovy Vary District, Karlovy Vary Region, Czech Republic. In a specimen from here aggregates of nickelskutterudite are abundant, occurring earlier than argentopyrite. Considerable associated proustite was also noted (AM 39.475-485).

In a specimen from Freiberg, Mittelsachsen, Saxony, Germany, argentopyrite was associated with gypsum, which appears as tiny crystals perched on a crust of argentopyrite and arsenic. Some proustite and occasional grains of pyrite were also observed (AM 39.475-485).

Common impurities: Cu,As

Back to Minerals