Bismuthinite

Bismuthinite

Bismuthinite - Schlaggenwald (Horni Slavkov) - Bohemia - Czech Republic (XX 1.1cm)
General
Category Sulfide mineral
Formula
(repeating unit)		 Bi2S3
Strunz classification 2.DB.05a
Crystal system Orthorhombic
Crystal class Dipyramidal (mmm)
H-M symbol: (2/m 2/m 2/m)
Space group Pbnm
Identification
Color Lead-gray to tin-white, with a yellowish or iridescent tarnish.
Crystal habit Slender prismatic to acicular, massive lamellar
Cleavage [010] Perfect
Fracture Brittle - sectile
Mohs scale hardness 2
Luster Metallic
Streak Lead grey
Specific gravity 6.8 - 7.2
Optical properties Opaque
References [1][2][3]

Bismuthinite is a mineral consisting of bismuth sulfide (Bi2S3). It is an important ore for bismuth. The crystals are steel-grey to off-white with a metallic luster. It is soft enough to be scratched with a fingernail and rather dense.

Bismuthinite forms a series with the lead, copper, bismuth mineral aikinite (PbCuBiS3).[3]

Bismuthinite crystal group from Bolivia (size: 2.9 x 1.9 x 1.5 cm)

It occurs in hydrothermal veins with tourmaline-bearing copper veins associated with granite, in some high temperature gold veins, and in recent volcanic exhalation deposits. Associated minerals include native bismuth, aikinite, arsenopyrite, stannite, galena, pyrite, chalcopyrite, tourmaline, wolframite, cassiterite and quartz.[1]

It was first reported in 1832 from the mines of Potosí, Bolivia.[2]

References

  1. 1 2 http://rruff.geo.arizona.edu/doclib/hom/bismuthinite.pdf Mineral Handbook
  2. 1 2 http://webmineral.com/data/Bismuthinite.shtml Webmineral Site
  3. 1 2 http://www.mindat.org/min-686.html Mindat mineral data

Further reading

Wikisource has the text of the 1911 Encyclopædia Britannica article Bismuthite.


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