Is there a specific “timing of mineralization” in gold deposits?
• The sulfide-related mobility of Au indicates that the approach to the history of a gold deposit must consider many intracrystalline mechanisms, which can make the age of mineralization inaccurate or untrue. • A review of the possible mechanisms of compositional zoning of Au (and other metals) in sulfides includes primary mineralization processes and processes associated with remobilization (quite common in most deposits). • The series of geological surveys of a deposit may imply the need or not to use geochronology to determine the “timing of mineralization”, which may be inadvisable in many cases. • An important result of this holistic exercise is that mineralization often cannot be attributed to a single, well-defined event, but reflects prolonged episodes of mineral growth and remobilization. Mineral chemistry, stable isotope geochemistry, deformation microstructures, and compositional zoning are keys to unravel the mineralization history of gold-bearing sulfide assemblages. As such, textural and compositional domains can represent (i) primary mineralization processes associated with crystallization and (ii) processes related to remobilization. Growth zonation can mark both fluid-rock interaction and the crystallization kinetics of sulfides, with implications on the oscillatory distribution of gold therein. For the latter, intra-grain migration of elements in the sulfide crystal structure can be attributed to several mechanisms and sub-mechanisms. Recognizing and distinguishing which mechanisms are responsible for the observed sulfide texture requires micro- to nanometer-scale spatial resolution analytical techniques. Such techniques can discern between several episodes of Au-bearing sulfide crystallization and remobilization, each contributing to highly different proportions of the overall gold budget. Thus, these mechanisms influence whether, how, and when gold is concentrated and consequently, they are key to our understanding of the effective “timing of gold mineralization.” By way of examples, we define a conceptual framework of how the intracrystalline transfer mechanisms of Au (and that of other metals) can inform about the history of a given deposit. An important outcome of this holistic exercise is that mineralization often cannot be ascribed to a single, well-defined event but reflects protracted episodes of mineral growth and remobilization.
Authors
- Wendell Fabricio-Silva (ORCID: https://orcid.org/0000-0002-5563-4866)
- María Emilia Schutesky (ORCID: https://orcid.org/0000-0001-8516-102X)
- Denis Fougerouse (ORCID: https://orcid.org/0000-0003-3346-1121)
- Alice Bosco‐Santos (ORCID: https://orcid.org/0000-0002-7357-8781)
- Fabrício de Andrade Caxito (ORCID: https://orcid.org/0000-0002-0335-3667)
- Carlos Alberto Rosière (ORCID: https://orcid.org/0000-0003-2364-6536)
- Hartwig E. Frimmel (ORCID: https://orcid.org/0000-0003-3041-8208)
Institutions
- Universidade Federal de Minas Gerais (BR)
- University of Cape Town (ZA)
- Curtin University (AU)
- Institute of Physics (AZ)
- Institute of Geography (KZ)
- University of Lausanne (CH)
Publication Details
- Journal
- Ore Geology Reviews
- Published
- 2025-05-06
- DOI
- https://doi.org/10.1016/j.oregeorev.2025.106663
- Citations
- 2
- Primary Topic
- Geological and Geochemical Analysis
- Type
- article
- Field-Weighted Citation Impact
- 3.73
Funders
- Coordenação de Aperfeiçoamento de Pessoal de Nível Superior