Froodit
Froodit | |
---|---|
General and classification | |
chemical formula | PdBi 2 |
Mineral class (and possibly department) |
Sulfides and sulfosalts |
System no. to Strunz and to Dana |
2.AC.45 ( 8th edition : II / D.21) 02.12.15.01 |
Crystallographic Data | |
Crystal system | monoclinic |
Crystal class ; symbol | 2 / m |
Space group | C 2 / m |
Lattice parameters |
a = 12.74 Å ; b = 4.29 Å; c = 5.71 Å β = 102 ° 27 ' Please complete the source as an individual reference |
Formula units | Z = 4 Please complete the source as an individual reference |
Physical Properties | |
Mohs hardness | 2.5 |
Density (g / cm 3 ) | 12.5 to 12.6 |
Cleavage | Completely |
Break ; Tenacity | irregular |
colour | Gray |
Line color | black |
transparency | opaque |
shine | metallic |
Froodit is a very rare mineral from the mineral class of sulfides and sulfosalts . It crystallizes in the monoclinic crystal system with the chemical composition PdBi 2 and forms flat, up to 4 mm large, exfoliated fragments and round grains of gray color.
Etymology and history
The mineral was discovered in 1958 by JE Hawley and LG Berry in the type locality , the Frood Mine in the Sudbury Basin in the Canadian province of Ontario . It is named after this too.
classification
In the Strunz system , Froodit is counted among the sulfides and sulfosalts. According to the 8th edition , together with Borishanskiit and Urvantsevit, it forms a group of sulfides with a ratio of metal to sulfur, selenium or tellurium of <1: 1. In the 9th edition it forms its own subgroup of compounds of semimetals with platinum group elements (PGE).
In the Dana systematics , it forms with Urvantsevit and Verbeekit a subgroup of sulfides, selenides and tellurides with the composition A m B n X p , with (m + n): p = 1: 2.
Education and Locations
Froodit forms in arsenic - lead - and copper - rich ores as well as in palladium - and platinum - containing ultramafic intrusions . It is associated with chalcopyrite , cubanite , pyrite , pentlandite , altaite , hessite , galena , bismuth , pyrrhotite , tsumoite , parkerite , sudburyite , michenerite , sperrylite , insizwait , niggliite , cabriite and mooihoekite .
Only a few sites are known of the very rare mineral. In addition to the type locality, Froodit was found in Whitehorse in Canada, Jinchuan in the Chinese province of Gansu , Havlíčkův Brod in the Czech Republic , Nivala in Finland , Norilsk and other sites in Russia , Insizwa and Rustenburg in South Africa , Kaisten in Switzerland , Newton Stewart in Scotland and Goodnews Bay in the US state of Alaska .
Crystal structure
Froodit crystallizes in the monoclinic crystal system in the space group C2 / m with the lattice parameters a = 12.74 Å ; b = 4.29 Å, c = 5.71 Å and β = 102 °, 27 'as well as four formula units per unit cell .
See also
Individual evidence
literature
- Froodit in: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( pdf; 64 kB ).