eCite Digital Repository

Microelectronic junctions in arsenian pyrite due to impurity and mixed sulfide heterogeneity

Citation

Laird, JS and MacRae, CM and Halfpenny, A and Large, R and Ryan, CG, Microelectronic junctions in arsenian pyrite due to impurity and mixed sulfide heterogeneity, American Mineralogist, 100, (1) pp. 26-34. ISSN 0003-004X (2015) [Refereed Article]

Copyright Statement

Copyright 2015 Mineralogical Society of America

DOI: doi:10.2138/am-2015-4648

Abstract

Impurities and crystal defects within the semiconducting bulk of a metal sulfide introduce energy levels within the forbidden bandgap. These levels in turn control semiconducting type and local electrical properties within single and multi-phased sulfide assemblages. Heterogeneity in sulfide semiconductivity linked to these impurities can lead to p-n micro-junction formation and potential distributions near the surface that may alter redox reactivity. Secondary gold ore genesis via a micro-galvanic effect related to heterogeneity has in the past been hypothetically linked to such micro-junctions. Understanding these regions and their interaction with weathering fluids in the regolith for example requires large-scale imaging of potential distributions associated with near-surface micro-junctions and correlation with the responsible elemental distributions. Here we investigate the existence of micro-electronic junctions in a mixed sulfide assemblage using scanning laser beam induced current (LBIC) and correlate them with pyrite-chalcopyrite interfaces mapped using combined energy-dispersive spectroscopy (EDS) and wavelength-dispersive spectroscopy (WDS) on an electron hyper-probe. Junctions in a natural assemblage are positively identified for the first time.

Item Details

Item Type:Refereed Article
Keywords:pyrite, heterogeneity, semiconductors, electrical properties, micro-junction, heterojunction, chalcopyrite, laser beam induced current, elemental mapping, metal ore genesis, electrochemical
Research Division:Earth Sciences
Research Group:Geology
Research Field:Ore Deposit Petrology
Objective Division:Mineral Resources (excl. Energy Resources)
Objective Group:Other Mineral Resources (excl. Energy Resources)
Objective Field:Mineral Resources (excl. Energy Resources) not elsewhere classified
Author:Large, R (Professor Ross Large)
ID Code:98219
Year Published:2015
Deposited By:Centre for Ore Deposit Research - CODES CoE
Deposited On:2015-02-05
Last Modified:2017-11-02
Downloads:0

Repository Staff Only: item control page