Next Article in Journal
Orebody Modeling from Non-Parallel Cross Sections with Geometry Constraints
Previous Article in Journal
Heat-Assisted Batch Settling of Mineral Suspensions in Inclined Containers
Article Menu

Export Article

Open AccessArticle
Minerals 2019, 9(4), 227; https://doi.org/10.3390/min9040227

Germanium Crystal Chemistry in Cu-Bearing Sulfides from Micro-XRF Mapping and Micro-XANES Spectroscopy

1
Université de Lorraine, CNRS, GeoRessources, F-54000 Nancy, France
2
Centre de Recherches Pétrographiques et Géochimiques (CRPG), Université de Lorraine, CNRS, UMR 7358, 15 Rue Notre Dame des Pauvres, BP 20, CEDEX, F-54501 Vandoeuvre-lès-Nancy, France
3
Geosciences Montpellier, Université de Montpellier, CNRS, CEDEX 5, 34095 Montpellier, France
4
European Synchrotron Radiation Facility, BP 220, F-38043 Grenoble, France
*
Author to whom correspondence should be addressed.
Received: 18 March 2019 / Revised: 8 April 2019 / Accepted: 9 April 2019 / Published: 12 April 2019
  |  
PDF [6476 KB, uploaded 16 April 2019]
  |  

Abstract

Germanium is considered a critical element, with a demand that has sharply increased due to booming high-technology industries. To understand Ge incorporation mechanisms in natural systems, we investigate Ge speciation in Cu-bearing sulfide minerals using synchrotron X-ray fluorescence (XRF) chemical mapping and Ge K-edge µ-X-ray absorption near-edge structures (µ-XANES) spectroscopy. The samples investigated include (i) a homogeneous chalcopyrite from the Kipushi polymetallic deposit (Central African copperbelt, D.R. Congo) and (ii) a zoned Ge-rich chalcopyrite from the Barrigão Cu deposit (Iberian pyrite belt, Portugal). First, our spectroscopic analysis supports the occurrence of tetrahedrally-coordinated Ge4+ in chalcopyrite, independently from origins or zoning patterns observed for these minerals. Then, based on statistical analyses of XRF chemical maps, we demonstrate that tetravalent germanium most likely incorporates chalcopyrite through the Fe crystallographic site via coupled substitutions with the following form: (2x + 3y)Fe3+ ⟷ (x + 2y)(Ge,Sn)4+ + x(Zn,Pb)2+ + y(Cu,Ag)+, although the presence of lattice vacancies cannot be completely excluded. View Full-Text
Keywords: micro-XANES; micro-XRF; Cu-bearing sulfides; germanium micro-XANES; micro-XRF; Cu-bearing sulfides; germanium
Figures

Figure 1

This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited (CC BY 4.0).
SciFeed

Share & Cite This Article

MDPI and ACS Style

Belissont, R.; Munoz, M.; Boiron, M.-C.; Luais, B.; Mathon, O. Germanium Crystal Chemistry in Cu-Bearing Sulfides from Micro-XRF Mapping and Micro-XANES Spectroscopy. Minerals 2019, 9, 227.

Show more citation formats Show less citations formats

Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Related Articles

Article Metrics

Article Access Statistics

1

Comments

[Return to top]
Minerals EISSN 2075-163X Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert
Back to Top