Indium-bearing sulfides from the Hämmerlein skarn deposit, Erzgebirge, Germany: evidence for late-stage diffusion of indium into sphalerite

At the Hämmerlein skarn deposit, located in the western Erzgebirge (Germany), a major cassiterite-dominated Sn mineralization stage is spatially associated with a younger Zn-Cu-In sulfide mineralization stage. In this contribution, we provide the first detailed description of the Zn-Cu-In sulfide mi...

Full description

Saved in:
Bibliographic Details
Published in:Mineralium deposita Vol. 54; no. 2; pp. 175 - 192
Main Authors: Bauer, Matthias E., Seifert, Thomas, Burisch, Mathias, Krause, Joachim, Richter, Nancy, Gutzmer, Jens
Format: Journal Article
Language:English
Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.02.2019
Springer Nature B.V
Subjects:
Bearing
Cassiterite
Chalcopyrite
Copper
Cracks
Diffusion
Dye dispersion
Earth and Environmental Science
Earth Sciences
Electron probe
Electron probe microanalysis
Electron probes
Enrichment
Fractures
Fronts
Geology
Grain boundaries
Haematite
Hematite
Indium
Magnetite
Mineral Resources
Mineralization
Mineralogy
Profiles
Sphalerite
Sulfides
Sulphides
Tin
Zinc
Zincblende
Germany
Sphalerite
Roquesite
Chalcopyrite
Indium
Diffusion
Skarn
ISSN:0026-4598, 1432-1866
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:At the Hämmerlein skarn deposit, located in the western Erzgebirge (Germany), a major cassiterite-dominated Sn mineralization stage is spatially associated with a younger Zn-Cu-In sulfide mineralization stage. In this contribution, we provide the first detailed description of the Zn-Cu-In sulfide mineralization stage, based on field geological observations combined with detailed petrographic studies and electron probe microanalysis data. Indium-rich sulfide mineralization occurs as irregular, semi-massive lenses or as infill of short, discontinuous veinlets that crosscut the cassiterite-bearing skarn assemblage. Indium- and Cu-rich sphalerite and roquesite are found to be closely associated with In-bearing chalcopyrite. The highest In concentrations in sphalerite occur at the rims and along cracks of sphalerite grains. The distribution resembles diffusion profiles, suggesting that the In enrichment is due to an hydrothermal overprint that postdates the initial formation of both sphalerite and chalcopyrite. Textural relations illustrate that the diffusion fronts in sphalerite grains are thicker where they are in contact to anhedral masses of hematite and magnetite. Our observations suggest that In enrichment in sphalerite at the Hämmerlein skarn deposit is due to the decomposition of In-bearing chalcopyrite. The resultant release of Fe led to the formation of hematite and magnetite, whereas Cu and In were incorporated into sphalerite along grain boundaries and micro fractures. Incorporation into the sphalerite lattice took place by coupled substitution of Cu +  + In 3+  ↔ 2Zn 2+ , suggesting that the concurrent availability of Cu and In may be an essential factor to enrich In in sphalerite in hydrothermal ore-forming environments.
Bibliography:ObjectType-Article-1
SourceType-Scholarly Journals-1
ObjectType-Feature-2
content type line 14
ISSN:0026-4598
1432-1866
DOI:10.1007/s00126-017-0773-1