Work

Is there a specific “timing of mineralization” in gold deposits?

Year: 2025

Type: article

Abstract: 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.

Source: Ore Geology Reviews

DOI: 10.1016/j.oregeorev.2025.106663