Stilleit
| Stilleit | |
|---|---|
| General and classification | |
| chemical formula | ZnSe |
|
Mineral class (and possibly department) |
Sulfides and sulfosalts |
|
System no. to Strunz and to Dana |
2.CB.05a ( 8th edition : II / C.01) 08/02/02/02 |
| Crystallographic Data | |
| Crystal system | cubic |
| Crystal class ; symbol | 4 3 m |
| Space group | F 4 3 m |
| Lattice parameters | a = 5.667 Å Please complete the source as an individual reference |
| Formula units | Z = 4 Please complete the source as an individual reference |
| Physical Properties | |
| Mohs hardness | 5 |
| Density (g / cm 3 ) | 5.42 |
| Cleavage | Please complete |
| colour | Gray |
| Line color | Please complete |
| transparency | opaque |
| shine | Please complete |
| Crystal optics | |
| Refractive indices | n α = 2.5 |
Stilleit , chemically zinc selenide is a very rarely occurring mineral from the mineral class of sulfides and sulfosalts . It crystallizes in the cubic crystal system with the chemical composition ZnSe and forms microscopic inclusions in linneite of gray color.
Etymology and history
Stilleit was first found in 1956 by Paul Ramdohr in the Shinkolobwe mine near Shinkolobwe in the Katanga province of the Democratic Republic of the Congo . He named it after the German geologist Hans Stille .
classification
In the Strunz system , Stilleit is one of the metal sulphides with a ratio of metal to sulfur, selenium or tellurium of 1: 1. After the 8th edition forms the sphalerite group together with Coloradoite , Hawleyite , Rudashevskyite , Polhemusite , Sphalerite , Metacinnabarite and Tiemannite . In the 9th edition it forms with these minerals and sakuraiite a subgroup of the sulfides with zinc , iron , copper or silver .
In the Dana systematics , it forms with coloradoite, hawleyite, rudashevskyite, sphalerite, metacinnabarite and tiemannite the sphalerite subgroup of sulfides, selenides and tellurides with the composition A m B n X p , with (m + n): p = 1: 1.
Education and Locations
Stilleit forms together with other selenides or as an inclusion in Linneit. Depending on where it was found, it is associated with pyrite , linnite, clausthalite , selenium vaesite , molybdenite and dolomite or tiemannite, clausthalite, eukairite , umangite and klockmannite .
Only a few locations of the mineral are known. In addition to the type locality in Katanga, Stilleit was also found near Sankt Andreasberg and Abberode in the Harz Mountains ( Germany ) and in several locations in the Argentine province of La Rioja .
Crystal structure
Stilleit crystallizes in the cubic crystal system in the space group with the lattice parameter a = 5.667 Å and four formula units per unit cell .
See also
Individual evidence
literature
- Stilleit in: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( pdf ).