Files and links (1)
CC BY-NC-ND V4.0, Open Access
Journal article
Pyrite records fluid evolution: sulfur sources controls on arsenic speciation and zonation
Geochemical perspectives letters, Vol.38, pp.53-59
2026
Abstract
Zoning and speciation of arsenic (As) in pyrite are used to infer changes in the chemical composition of hydrothermal fluids and conditions of ore deposit formation. Yet, the processes controlling the distribution and oxidation state of As during pyrite formation are poorly understood. We report the results of experiments designed to test the capacity of pyrite to record changes in fluid composition under dynamic reaction conditions. When pyrite seeds were exposed alternately to As-bearing and As-free fluids, concentric As-rich (≤6.0 wt. % of As1−) and As-free pyrite overgrowths formed when native S was used as the sulfur source. In contrast, a sodium thiosulfate source produced randomly oriented aggregates of concentrically zoned microparticulate (∼1 μm) As-bearing pyrite (<1.5 wt. % of As2+/3+), failing to record the changes of fluid composition. We demonstrate that by controlling H2S(aq) availability, the source of sulfur affects the degree of pyrite supersaturation under conditions relevant to natural hydrothermal systems, which controls the nucleation rate, crystal growth, As uptake, As oxidation state, and consequently, the ability of pyrite to record individual fluid pulses. This sulfur source effect has significant implications for metal incorporation into pyrite and understanding of the formation of many ore deposits.
Details
- Title
- Pyrite records fluid evolution: sulfur sources controls on arsenic speciation and zonation
- Authors/Creators
- A. P. Deditius - Murdoch University, Centre for Water, Energy and WasteX. Yao - Sustainable Geochemistry and Mineral Sciences, School of Mathematics, Statistics, Chemistry and Physics, Murdoch University, Perth, WA, AustraliaF. Xia - Murdoch University, School of Mathematics, Statistics, Chemistry and PhysicsJ. Brugger - School of Earth, Atmosphere and the Environment, Monash University, Clayton, VIC, AustraliaY. Xing - CSIRO Mineral Resources, Clayton, VIC, AustraliaB. E. Etschmann - School of Earth, Atmosphere and the Environment, Monash University, Clayton, VIC, AustraliaA. Suvorova - Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, WA, AustraliaM. P. Roberts - Centre for Microscopy, Characterisation and Analysis, The University of Western Australia, Perth, WA, AustraliaC. M. Kewish - Australian Synchrotron, Clayton, VIC, Australia
- Publication Details
- Geochemical perspectives letters, Vol.38, pp.53-59
- Publisher
- European Association of Geochemistry
- Number of pages
- 7
- Grant note
- DP220100500 / Australian Research Council (501100000923) DP170101893; DP220100500 / Australian Research Council (http://data.elsevier.com/vocabulary/SciValFunders/501100000923) University of Western Australia (http://data.elsevier.com/vocabulary/SciValFunders/501100001801) Australian Research Council (http://data.elsevier.com/vocabulary/SciValFunders/501100000923) DP170101893 / Australian Research Council (501100000923)
- Identifiers
- 991005869302707891
- Copyright
- © 2026 The Authors
- Murdoch Affiliation
- School of Mathematics, Statistics, Chemistry and Physics; Centre for Water, Energy and Waste
- Language
- English
- Resource Type
- Journal article
Metrics
1 File views/ downloads
2 Record Views