This article documents the new precipitates formed related to acid mine drainage (AMD) at Dabaoshan mine (South China). X-ray diffraction (XRD), Fourier Transform Infrared Spectroscopy (FTIR) and Scanning Electron Microscope & Energy Spectrometer (SEM-EDS) have been used to detect minerals in AMD impoundment and downstream creeks. The occurrences, the mineralogical species and the micro-morphological characteristics of secondary minerals from different pH conditions has been carried out. Iron- hydroxysulfates and iron-oxyhydroxides are the main secondary minerals, and they occurred as both poorly and well-crystalline minerals. Jarosite nearly predominate as pseudocubic crystals at pH 2.5–4.0. Schwertmannite-rich sediments occurred at pH 3.82–4.5 as urchin-like, pin-cushion and as well as globular-like aggregates and show high concentrations of Mn, Cu, Pb and As due to adsorption and co-precipitation. Goethite formed mainly as botryoidal and flaky assemblages. Paragenesis of different types of schwertmannite indicate that pH condition is not the dominant factor controlling morphology but the main parameter for the variation of minerals species. Statistical analysis reveal obvious changing tendency in Zn, Cd and SO₄ within pH. FTIR analysis show adsorption of Cu, Pb, Zn and As on secondary iron minerals. Water elements with high concentrations in the impoundment and the obvious decrease in downstream creak reflected an accumulation and evaporation in AMD impoundment and a dilution in downstream area respectively. These results indicate that secondary minerals associated with AMD can play an important role in attenuating toxic elements.

本文记录了与大宝山矿山（华南）酸性矿山排水（AMD）有关的新沉淀物。X射线衍射（XRD），傅立叶变换红外光谱（FTIR）和扫描电子显微镜和能谱仪（SEM-EDS）已用于检测AMD蓄水区和下游小溪中的矿物。研究了不同pH条件下次生矿物的发生，矿物学种类和微观形态特征。羟基硫酸铁和羟基氧化铁是主要的次要矿物质，它们既是贫矿又是结晶度好的矿物质。在pH值为2.5-4.0时，黄铁矿几乎是伪立方晶体。富含Schwertmannite的沉积物在pH为3.82–4.5时呈海胆状，枕形和球状聚集体由于吸附和共沉淀而显示出高浓度的Mn，Cu，Pb和As。针铁矿主要以类葡萄状和片状组合形式形成。不同类型的Schwertmannite的共生表明，pH条件不是控制形态的主要因素，而是矿物质种类变化的主要参数。统计分析表明锌，镉和SO有明显的变化趋势pH在₄以内。FTIR分析表明，Cu，Pb，Zn和As吸附在次生铁矿物上。蓄水池中高浓度的水元素和下游吱吱声的明显减少分别反映了AMD蓄水池的积累和蒸发以及下游区域的稀释。这些结果表明，与AMD相关的次要矿物质可以在减弱有毒元素方面发挥重要作用。