Mobilization of Au and Ag during Supergene Processes in the Linglong Gold Deposit: Evidence from SEM and LA–ICP–MS Analyses of Sulfides

Precious metals can be mobilized during supergene processes, which are important for the formation of high-grade or high-purity ores. The world-class Linglong gold deposit has ores that have undergone processes in near-surface zone. Under conditions modification occurred and how Au Ag behaved been poorly studied this deposit. Here, we performed scanning electron microscope (SEM) laser ablation–inductively coupled plasma–mass spectrometry (LA–ICP–MS) analyses on samples from enrichment zone results show secondary minerals were formed sequentially magnetite-goethite-limonite to marcasite-acanthite, finally siderite after primary pyrite-pyrrhotite-chalcopyrite. These mineral assemblages variations indicate by groundwater under oxidative weakly acidic evolved reductive near neutral newly marcasite much higher (0.003–23.5 ppm, mean 1.33 ppm) (81.7–6021 1111 concentrations than those pyrite (Au 0.004–0.029 ppm 0.22–4.14 ppm), together with independent Ag–S (acanthite), indicates significantly fractionated processes. improved grades thus facilitate their extraction.