General Information:
Chemical Formula:
TlCu(Zn,Fe,Hg)2As2S6
Environment:
In small cavities of hydrothermal origin in Triassic dolomite.
IMA Status:
Approved IMA 1987
Locality:
Lengenbach, Binntal, Canton Wallis, Switzerland.
Name Origin:
For Prof. Dr. Hans A. Stalder (1925-) of the Natural History Museum, Berne, Switzerland.
Physical Properties:
Cleavage:
None
Color:
black, reddish black, or bluish black.
Density:
4.97
Diaphaniety:
Opaque
Habits:
Euhedral Crystals - Occurs as well-formed crystals showing good external form., Crystalline - Fine - Occurs as well-formed fine sized crystals.,
Hardness:
3.5-4 - Copper Penny-Flourite
Luminescence:
Non-fluorescent.
Luster:
Metallic
Streak:
brownish red
More details...