Electrical micro-junctions in metal sulfides drive electrochemical reactions with passing gold-bearing fluids, resulting in the deposition of gold, even from under-saturated ore fluids. Understanding the role micro-junctions play in the deposition of gold requires (a) imaging the electric field distribution of a galvanic couple near the surface to qualify the existence of an active micro-geo-battery and (b) correlating it with gold precipitation on the p-type cathode side of the junction by mapping the host at minor and trace levels. Here we report on correlating electron back scattered diffraction (EBSD), particle induced X-ray emission (PIXE) elemental maps including micron-scaled gold hot spots with laser beam induced current (LBIC) photocurrent maps of galvanic coupling in natural arsenian pyrite from the Otago Schist in New Zealand. The results provide convincing evidence that sulphide electrochemical interactions can lead to gold electro-deposition. We finish by discussing a simplistic model of the processes involved in reference to the original model of Möller and Kersten (Miner Deposita 29(5):404–413. 1994), and discuss the effects of temperature in light of recent-reported evidence of electrochemical gold deposition in the formation of hydrothermal gold deposits.

金属硫化物中的电微结会驱动通过的含金流体发生电化学反应，从而导致金的沉积，即使是来自饱和度较低的矿液也是如此。要了解微结在金的沉积中所起的作用，需要（a）对表面附近的电偶的电场分布进行成像，以限定活性微地电池的存在，以及（b）将其与金矿上的金沉淀相关联。通过将主体映射在次要和痕量水平来实现结的p型阴极侧。在这里我们报告相关的电子背散射衍射（EBSD），包括微米级金热点的粒子诱导X射线发射（PIXE）元素图与天然砷黄铁矿中电流耦合的激光束诱导电流（LBIC）光电流图的相关性。奥塔哥·史斯特（Otago Schist）在新西兰。结果提供了令人信服的证据，表明硫化物的电化学相互作用可导致金的电沉积。最后，我们讨论涉及Möller和Kersten原始模型的过程的简化模型（Miner Deposita 29（5）：404–413。1994），并根据最近报告的温度证据讨论温度的影响。电化学金的沉积形成热液金矿床。