Freibergite

Freibergite is a complex sulfosalt mineral of silver, copper, iron, antimony and arsenic with formula (Ag,Cu,Fe)₁₂(Sb,As)₄S₁₃. It has cubic crystals and is formed in hydrothermal deposits. It forms one solid solution series with tetrahedrite and another with argentotennantite. Freibergite is an opaque, metallic steel grey to black and leaves a reddish black streak. It has a Mohs hardness of 3.5 to 4.0 and a specific gravity of 4.85 - 5. It is typically massive to granular in habit with no cleavage and an irregular fracture.

Additional recommended knowledge

Safe Weighing Range Ensures Accurate Results

Recognize and detect the effects of electrostatic charges on your balance

Weighing the right way

The mineral was first described in 1853 from an occurrence in the silver mines of the type locality at Freiberg, Saxony.

References

• Mineral handbook
• Webmineral
• Mindat