Trace element mapping of pyrite from Archean gold deposits - A comparison between PIXE and EPMA
Chemical zoning of pyrites can record the evolution of mineralising fluids at widely varying P-T conditions ranging from diagenesis to medium-grade metamorphism. If preserved, zoning can reveal growth textures, brecciation and veining, resorption and recrystallisation events, thus shedding light on...
| Main Authors: | , , |
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| Format: | Journal Article |
| Published: |
Elsevier
2015
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| Online Access: | http://hdl.handle.net/20.500.11937/36156 |
| _version_ | 1848754691464232960 |
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| author | Agangi, Andrea Przybylowicz, W. Hofmann, A. |
| author_facet | Agangi, Andrea Przybylowicz, W. Hofmann, A. |
| author_sort | Agangi, Andrea |
| building | Curtin Institutional Repository |
| collection | Online Access |
| description | Chemical zoning of pyrites can record the evolution of mineralising fluids at widely varying P-T conditions ranging from diagenesis to medium-grade metamorphism. If preserved, zoning can reveal growth textures, brecciation and veining, resorption and recrystallisation events, thus shedding light on the processes that contributed to ore formation. Chemical zoning of sulfides is invisible in optical microscopy, but can be studied by chemical etching, high-contrast back-scattering electron images, and elemental imaging. In this study we compared micro-PIXE and WDS-EPMA elemental maps on the chemically zoned pyrites in mineralised vein-bearing samples from the Sheba and Fairview gold mines in the Barberton Greenstone Belt, South Africa. Elemental images show complex distribution of trace elements, suggesting multiple events of pyrite crystallisation and gold deposition. EPMA maps show fine-scale variations reflecting growth and recrystallisation textures marked, in particular, by variations of As, Ni, and Co. In PIXE maps, gold occurs both as finely-distributed and discrete inclusions, suggesting incorporation in the pyrite structure as solid solution, and deposition as electrum inclusions, respectively. Micro-PIXE and EPMA provide complementary information, forming together a powerful tool to obtain information on chemical zoning of pyrites in ore deposits. |
| first_indexed | 2025-11-14T08:44:26Z |
| format | Journal Article |
| id | curtin-20.500.11937-36156 |
| institution | Curtin University Malaysia |
| institution_category | Local University |
| last_indexed | 2025-11-14T08:44:26Z |
| publishDate | 2015 |
| publisher | Elsevier |
| recordtype | eprints |
| repository_type | Digital Repository |
| spelling | curtin-20.500.11937-361562017-09-13T15:36:21Z Trace element mapping of pyrite from Archean gold deposits - A comparison between PIXE and EPMA Agangi, Andrea Przybylowicz, W. Hofmann, A. Chemical zoning of pyrites can record the evolution of mineralising fluids at widely varying P-T conditions ranging from diagenesis to medium-grade metamorphism. If preserved, zoning can reveal growth textures, brecciation and veining, resorption and recrystallisation events, thus shedding light on the processes that contributed to ore formation. Chemical zoning of sulfides is invisible in optical microscopy, but can be studied by chemical etching, high-contrast back-scattering electron images, and elemental imaging. In this study we compared micro-PIXE and WDS-EPMA elemental maps on the chemically zoned pyrites in mineralised vein-bearing samples from the Sheba and Fairview gold mines in the Barberton Greenstone Belt, South Africa. Elemental images show complex distribution of trace elements, suggesting multiple events of pyrite crystallisation and gold deposition. EPMA maps show fine-scale variations reflecting growth and recrystallisation textures marked, in particular, by variations of As, Ni, and Co. In PIXE maps, gold occurs both as finely-distributed and discrete inclusions, suggesting incorporation in the pyrite structure as solid solution, and deposition as electrum inclusions, respectively. Micro-PIXE and EPMA provide complementary information, forming together a powerful tool to obtain information on chemical zoning of pyrites in ore deposits. 2015 Journal Article http://hdl.handle.net/20.500.11937/36156 10.1016/j.nimb.2014.11.070 Elsevier restricted |
| spellingShingle | Agangi, Andrea Przybylowicz, W. Hofmann, A. Trace element mapping of pyrite from Archean gold deposits - A comparison between PIXE and EPMA |
| title | Trace element mapping of pyrite from Archean gold deposits - A comparison between PIXE and EPMA |
| title_full | Trace element mapping of pyrite from Archean gold deposits - A comparison between PIXE and EPMA |
| title_fullStr | Trace element mapping of pyrite from Archean gold deposits - A comparison between PIXE and EPMA |
| title_full_unstemmed | Trace element mapping of pyrite from Archean gold deposits - A comparison between PIXE and EPMA |
| title_short | Trace element mapping of pyrite from Archean gold deposits - A comparison between PIXE and EPMA |
| title_sort | trace element mapping of pyrite from archean gold deposits - a comparison between pixe and epma |
| url | http://hdl.handle.net/20.500.11937/36156 |