Genkinit

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Genkinit
General and classification
other names

IMA 1976-051

chemical formula (Pt, Pd) 4 Sb 3
Mineral class
(and possibly department)
Sulfides and sulfosalts
System no. to Strunz
and to Dana
2.AC.35 ( 8th edition : II / A.05)
06/02/04/01
Crystallographic Data
Crystal system tetragonal
Crystal class ; symbol 422
Lattice parameters a  = 7.736  Å ; c  = 24.161 Å Please complete the source as an individual reference!
Formula units Z  = 8 Please complete the source as an individual reference!
Physical Properties
Mohs hardness 5.5 to 6
Density (g / cm 3 ) 9.256
Cleavage Please complete!
colour pale brown
Line color Please complete!
transparency opaque
shine metallic

Genkinit is a very rarely occurring mineral from the mineral class of sulfides and sulfosalts . It crystallizes in the tetragonal crystal system with the chemical composition (Pt, Pd) 4 Sb 3 and forms irregularly shaped grains of up to 165 μm in size and pale brown in color.

Etymology and history

The mineral was described in 1974 by LJ Cabri, JM Stewart, JHG Laflamme and JT Szymański in the Onverwacht mine near Rustenburg in South Africa ( type locality ) and named after the Russian mineralogist Alexandr Dimitrievich Genkin (1920-2010), who discovered many platinum group minerals.

classification

In the Strunz system , Genkinit is one of the alloys and alloy-like compounds, a subgroup of sulfides and sulfosalts. After the 8th edition it forms a group together with arsenopalladinite , athenite , itoigawaite , mayakite , menshikovite , mertieite-I , mertieite-II , pallado arsenide , palladobismuto arsenide , palladodymite , polkanovite , rhodarsenide , stibiopalladinite , stillwaterite , ungavaite and vincentine . In the 9th edition it forms with Ungavait a subgroup of the compounds of semimetals with platinum group elements (PGE).

The systematics of minerals according to Dana , which is mainly used in the English-speaking world , assigns the genenkinite to the common class of "sulfides" and there in the department of "sulfide minerals". Here he is with Oulankait and Ungavait in the " Genkinitgruppe " within the subdivision "sulphides - with the composition on Bn Xp, with (m + n) - including selenides and tellurides: p = 4: 3" to find.

Education and Locations

Genenkinite forms in ultramafitites and ophiolites , which contain platinum , iron , copper and nickel . Depending on where it was found , it is associated with sperrylite , platarsite , ruthenarsenite , stibiopalladinite , mertieite-II , platinum-iron alloys and chromite , or osmium , platinum- palladium- copper alloys, hollingworthite , irarsite , laurite and chromite.

Only a few locations are known of the very rare mineral. In South Africa , Genkinit was found in addition to its type locality at Burgersfort in the Bushveld Complex , Gimbi in Ethiopia , the Shetland Islands Fetlar and Unst and Goodnews Bay in the US state of Alaska .

Crystal structure

Genkinit crystallizes in the tetragonal crystal system with the lattice parameters a = 7.736  Å and c = 24.161 Å, as well as eight formula units per unit cell .

See also

Individual evidence

  1. Alexandr Dimitrievich Genkin (1920–2010). In: The Canadian Mineralogist. Volume 48.5 (2010), p. 1317 doi : 10.3749 / canmin.48.5.1317 and Mindat - obituary for Aleksandr Dmitrievich Genkin (1919-2010) (English)

literature

  • Genkinit in: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( pdf ).

Web links