Krennerite - Encyclopedia
Class : Sulfides and sulfosalts
Subclass : Tellurides
Crystal system : Orthorhombic
Chemistry : Au3AgTe8
Rarity : Rare to very rare
Krennerite is a rare hydrothermal mineral from gold-bearing epithermal veins where it accompanies native gold and other tellurides (petzite, sylvanite, hessite). It is one of the rarest tellurides. It was named in honor of the Hungarian mineralogist Joseph A. Krenner who was responsible for the first description of the mineral. The krennerite crystals form stubby prisms ridged parallel to [001]. It is a mineral with an intense metallic luster, silver-white in color, tarnishing to a pale brass yellow. It decomposes under surface conditions, releasing films of native gold. Its silver content can exceed 5%. It is a very incidental gold ore.
Main photo : 3.6 cm krennerite from Emperor Mine, Fidji Islands © Rock Currier
Krennerite in the World
Twinning
No twins known for this mineral species.
Fakes and treatments
No fakes recorded for this mineral species.
Hardness : 2 to 3
Density : 8.62
Fracture : Irregular to sub-conchoidal
Streak : Silver white
TP : Opaque
RI : -
Birefringence : -
Optical character : -
Pleochroism : None
Fluorescence : None
Solubility : -
Magnetism : NoneRadioactivity : None