Three-dimensional and microstructural fingerprinting of gold nanoparticles at fluid-mineral interfaces

Haoyang Zhou, Richard Wirth, Sarah A. Gleeson, Anja Schreiber, Sathish Mayanna - GFZ German Research Centre for Geosciences / Institute of Geological Sciences, Freie Universität Berlin

Recent studies have identified gold nanoparticles in ores in a range of deposit types, but little is known about their formation processes. In this contribution, gold-bearing magnetite from the well-documented, world-class Beiya Au deposit, China, was investigated in terms of microstructure and crystallography at the nanoscale. We present the first three-dimensional (3D) focused ion beam/scanning electron microscopy (FIB/SEM) tomography of the distribution of gold nanoparticles in nanopores in the low-Si magnetite.