九曲矿床位于胶东玲珑金矿田东部，属于典型的“石英脉型”金矿床。黄铁矿作为该矿床中主要的载金矿物和成矿期的贯通性矿物，其矿物学特征对该区矿床成因和找矿预测均具有重要意义。通过研究不同成矿阶段的黄铁矿矿相学发现：九曲金矿床中细粒状、破碎状和裂纹状黄铁矿对金富集具有重要的指示意义；黄铁矿中的自然金主要有晶隙金、裂隙金和包体金3种类型；浅黄色、暗黄色或黄色黄铁矿中金含量较高。不同成矿阶段的黄铁矿微区地球化学特征研究显示：黄铁矿主量元素总体表现为富铁贫硫特征，含矿流体在上升过程中硫逸度逐渐降低；第一、四阶段的微量元素总量小于第二、三主成矿阶段，指示成矿热液的温度由早期阶段到主成矿阶段总体有降低的趋势。黄铁矿复杂聚形、颜色变化、黄铁矿中脆性和塑性变形特征均可作为找矿标志。

Jiaodong gold province is one of the major gold producing areas in China.Linglong gold orefield is located in the northwestern Jiaodong，which is a typical representative of the super large quartz-vein type gold orefields.In recent years，many scholars have carried out detailed geological prospecting and genesis of the Linglong gold orefield，but there are still controversies about the sources of ore-forming materials and fluids，and the mechanism of gold mineralization.Besides，deep exploration of gold ore is urgently needed to be solved.In this study，the Jiuqu gold deposit，located in the eastern part of the Linglong gold orefield，were sampled.The study of pyrite，the main gold-bearing mineral in the Jiuqu gold deposit，is of great significance to the genesis and prospecting prediction of the deposit. The mineral graphical and micro-geochemical characteristics of pyrite in different metallogenic stages were studied in detail，such as pyrite-quartz stage，quartz-pyrite stage，quartz polymetallic sulfide stage and carbonate stage.Mineralogy studies have found that there are three main types of native gold associated with pyrite in the Jiuqu gold deposit，mainly including intergranular gold and inclusion gold，with locally appearing of a large amount of fissure gold.The pentagonal dodecahedron of pyrite and its complex aggregates are usually related to the sulfur-rich concentration of ore-forming fluids，which is one of the good signs of gold mineralization.The crushing degree and particle size of pyrite are closely related to the content of primary gold，implying that pyrites with higher crushing degree and smaller particle size have a larger specific surface area，which is conducive to the adsorption of gold.Light-yellow，dark-yellow or yellow pyrite usually contain higher gold contents，while light-yellow white pyrite has a relatively low gold content.The micro-geochemical characteristics of pyrite show that the major elements of pyrite are characterized by iron-rich and sulfur-poor，and that the sulphur fugacity of the ore-bearing fluid gradually decreases during the ascending process.The difference in the chemical structure of pyrite indicates that it has experienced a lot of brittleness and plastic microstructural deformation.Moreover，the temperature of ore-forming hydrothermal fluids from the early stage to the main ore-forming stage generally tends to decrease.According to the mineralogy and mineral geochemical characteristics of the gold-bearing pyrite in the Jiuqu gold deposit，pyrite has a certain indication of ore-forming significance.Pyrite with complex shape，color change，brittleness and plastic deformation charac-teristics of pyrite can be used as prospecting indicators.

http://www.goldsci.ac.cn/article/2020/1005-2518/1005-2518-2020-28-3-328.shtml

中国地质大学（北京）邱昆峰副教授在本文撰写过程中给予了大量的指导，提出了许多修改意见；北京科技大学梁亚运讲师在野外采样以及文章撰写过程中提供了诸多指导；中国地质大学（北京）马遥博士在样品采集、分析测试以及文章修改过程中均给予大量帮助；审稿人提出了宝贵的修改意见，在此一并表示感谢！