Baumhauerite - Encyclopedia
Class : Sulfides and sulfosalts
Subclass : Sulfosalts
Crystal System : Triclinic
Chemistry : Pb3As4S9
Rarity : Very rare
Bauhauerite is a very rare lead sulfoarsenide of hydrothermal origin, known from less than 10 deposits in the world. Its name was given to it in honor of Heinrich Adolph Baumhauer, professor of mineralogy at the University of Friborg (Switzerland). Its crystals are short prismatic or tabular, frequently striated and measure up to 2.5 mm. Baumhauerite also occurs in aggregates of rounded grains. A dark gray color that tarnishes on air, baumhauerite is very difficult to distinguish from other lead sulfoarsenides by simple means.
Main photo : Baumhauerite from Lengenbach, Binn, Valais, Switzerland © Enrico Bonacina
Baumhauerite in the World
Twinning and special crystallizations
Polysynthetic twins on {100} are known.
Fakes and treatments
No fake or treatment identified for this mineral species.
Hardness : 3
Density : 5.33 to 5.44
Fracture : Conchoidal
Trace : Brown
TP : Opaque
RI : -
Birefringence : -
Optical character : -
Pleochroism : None
Fluorescence : None
Solubility : -
Magnetism : None
Radioactivity : None