Palarstanid
| Palarstanid | |
|---|---|
| General and classification | |
| other names |
IMA 1976-058 |
| chemical formula | Pd 8 (Sn, As) 3 |
|
Mineral class (and possibly department) |
Sulfides and sulfosalts |
|
System no. to Strunz and to Dana |
2.AC.20 ( 8th edition : I / A.16) 03/02/03/02 |
| Crystallographic Data | |
| Crystal system | hexagonal |
| Crystal class ; symbol | Please complete |
| Lattice parameters | a = 7.50 Å ; c = 10.34 Å Please complete the source as an individual reference |
| Formula units | Z = 3 Please complete the source as an individual reference |
| Physical Properties | |
| Mohs hardness | 5 |
| Density (g / cm 3 ) | 10.27 |
| Cleavage | perfectly along {0001} |
| Break ; Tenacity | brittle |
| colour | steel gray |
| Line color | Please complete |
| transparency | opaque |
| shine | metallic |
Palarstanide is a very rare mineral from the mineral class of sulphides and sulphosalts . It crystallizes in the hexagonal crystal system with the chemical composition Pd 8 (Sn, As) 3 and forms hexagonal prisms or elongated, rectangular, more rarely wave-shaped grains of up to 1.5 mm in size and of a steel-gray color.
Etymology and history
The mineral was found in 1981 by WD Begisow, JM Sawjalow and JG Pavlov in its type locality , the Mayak mine near Norilsk in Russia . It was named after the elements palladium , arsenic and tin (lat. Stannum) it contained.
classification
In the Strunz system , the classification of the Palarstanides differs depending on the edition. After the 8th edition , together with atokite , niggliite , plumbopalladinite , rustenburgite , stannopalladinite and zvyagintsevit, it forms a group of metals, alloys and intermetallic compounds that belong to the mineral class of elements. In the 9th edition it forms with arsenopalladinite , mertieite-II and stillwaterite a subgroup of the compounds of semimetals with platinum group elements (PGE), which are classified under sulfides and sulfosalts.
In the systematics according to Dana , which is mainly used in the English-speaking world , it forms with stibiopalladinite a subgroup of sulfides, selenides and tellurides with the composition A m B n X p , with (m + n): p = 5: 2.
Education and Locations
Palarstanide forms as an intergrowth with other minerals in cubanite , chalcopyrite or talnakhite ores. It is associated with pentlandite , rustenburgite - atokite , platinum - iron alloys, polarite , sperrylite , mayakite , and gold - silver - copper alloys.
Only a few locations are known of the very rare mineral. In addition to its type locality, palarstanide was only found in the Stillwater complex in the US state of Montana .
Crystal structure
Palarstanide crystallizes in the hexagonal crystal system with the lattice parameters a = 7.50 Å and c = 10.34 Å and three formula units per unit cell .
See also
Individual evidence
literature
- Palarstanid in: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( pdf ).