Galenobismutite

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Galenobismutite
Galenobismutite in pyrite and quartz - Mühlleithen, Vogtland.jpg
Galenobismutite in pyrite and quartz
General and classification
chemical formula PbBi 2 S 4
Mineral class
(and possibly department) 		Sulfides and sulfosalts
System no. to Strunz
and to Dana 		2.JB.45 ( 8th edition : II / E.34)
07/03/09/01
Crystallographic Data
Crystal system orthorhombic
Crystal class ; symbol mmm
Space group Pnam
Lattice parameters a  = 11.669  Å ; b  = 14.533 Å; c  = 4.090 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 2.5 to 3
Density (g / cm 3 ) 7.04
Cleavage well along {110}
Break ; Tenacity irregular / uneven
colour lead gray, gray, light gray, tin white
Line color grey black
transparency opaque
shine metallic

Galenobismutite is a rare mineral from the mineral class of sulfides and sulfosalts . It crystallizes in the orthorhombic crystal system with the chemical composition PbBi 2 S 4 and forms elongated, needle-like crystals or thin plates up to one centimeter in size. It is from light gray to pewter white in color.

Etymology and history

The mineral was first found and described in 1878 by Hjalmar Sjögren in the Ko mine in Värmland , Sweden . It is named after its constituents, the mineral galena and the element bismuth .

classification

In the Strunz system , galenobismutite is classified as sulfides and sulfosalts. It is counted among the sulfo salts. In the 8th edition he formed a group with Cannizzarit , Cosalit , Felbertalit , Junoit , Mozgovait , Nordströmmit , Paderait , Proudit , Weibullit and Watkinsonit . In the 9th edition , the sulfo salts are divided into two main groups, which are named after the model sulfides (lead or zinc sulfide). Galenobismutite forms a subgroup of galena derivatives with lead with Ángelaite and Weibullite.

In the systematics of minerals according to Dana , galenobismutite forms a subgroup of sulfosalts with sakharovaite , berthierite , garavellite and klerite with the ratio z / y = 2 and the composition (A + ) i (A 2+ ) j [B y C z ], A = metals, B = semi-metals, C = non-metals.

Modifications and varieties

It is a known silver-containing variety found in the Chinese province of Ganzhou .

Education and Locations

The mineral forms under hydrothermal conditions. It is associated with galena, bismuth, cosalite, aikinite , tellurobismutite , joseit , tetradymite , tetrahedrite , gold , pyrite and quartz . Solid gold can be found in grains up to one millimeter in size embedded in galenobismutite.

A large number of Galenobismutite sites are known. In addition to the type locality near Nordmark and other finds in Sweden, there are finds from the Oberpinzgau in Austria , Pechtelsgrün in Saxony , Somerset and Cornwall in England , Kingsgate and Mt. Farrell in Australia , Chenzhou in China; Mines in Idaho and Washington , United States ; British Columbia , Ontario and Yukon Territory in Canada , Cerro Bonete in Bolivia and smaller occurrences.

Crystal structure

Galenobismutite crystallizes in the orthorhombic crystal system in the space group Pnam with the lattice parameters a = 11.669  Å , b = 14.533 Å and c = 4.090 Å as well as four formula units per unit cell .

See also

Individual evidence

  1. ↑ a b Naturhistoriska riksmuseet: Mer om Galenobismutit ( Memento of November 21, 2008 in the Internet Archive ), accessed on October 23, 2009 (Swedish).
  2. ^ List of minerals according to Dana at webmineral.com
  3. ↑ Argentiferous Galenobismutite at mindat.org (Eng.).

literature

  • Galenobismutite in: Anthony et al .: Handbook of Mineralogy , 1990, 1, 101 ( pdf )
  • H. Sjögren: Om några vismutmineralier från Nordmarks grufvor i Vermland - III. Ett nytt vismutsvafladt svafvelbly . In: Aftryck ur Geol. Förenigens i Stockholm Förhandl . 1878, 46, 4, pp. 109-111, pdf (Swedish).

Web links

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