In this paper electron microprobe analyzer (EMPA) and scanning electron microscopy were used (SEM) to investigate the content, distribution and concentrations of Au, As, S, Fe and Sb in the gold-bearing minerals of different ore-forming stages in the Miaolong Carlin-type gold-antimony deposit. Arsenian pyrite and arsenopyrite are recognized as the most important gold-bearing minerals in this deposit. The values of sulfur and iron in pyrite formed at the sedimentary rock-forming stage are close to their theoretical values, whereas the sulfur values of the pyrite formed at the early metallogenic stage and the core of annulus pyrite at the S1 sub-stage of the main metallogenic stage are close to the theoretical value where the iron content of core of annulus pyrite is characterized by weak losses. The values of sulfur and iron in the outer rings of annulus pyrite are characterized by weak depletion. The pyrite of the sedimentary rock-forming stage is framboidal and contains no arsenic or antimony. The content of gold is low, with an average of 59 × 10-6. The coarse-grained pyrite (≥100μm) formed at the early hydrothermal rock-forming stage is low in As and Au, with their values being 0.205% and 0.00275% on average. The outer ring of the zonal fine-grained pyrite (<50μm, mainly about 10-20μm) formed at the S1 sub-stage of the main hydrothermal ore-forming period is rich in As and Au. The values of As are 0.1961%-7.897%with an average of 1.4668%and the values of Au are 40×10-6-905×10-6 with an average of 429×10-6. The arsenopyrite formed at the S2 sub-stage is characterized by enrichment of sulfur and depletion of arsenic. The values of Au are 230×10-6-1400×10-6 with an average of 643×10-6, and the values of Sb are 0.019%-0.50%with an average of 0.087%. The values of Au in stibnite formed at the late stage is low, with an average of 237 × 10-6. The values of Au from sedimentary rock-forming stage→early ore-forming stage→main ore-forming stage→late ore-forming vary in order of low or none→low→high→low. Au exists as isomorph (solid solution) in arsenopyrite and pyrite.%提采用电子探针和扫描电镜分析,通过对贵州苗龙卡林型金-锑矿床矿石中不同成矿阶段载金矿物的Au、As、S、Fe和Sb等元素含量及其分布规律的详细研究,确定了含砷环带黄铁矿和毒砂是最重要的载金矿物。成岩期黄铁矿S、Fe含量与理论值接近,成矿期早阶段黄铁矿和主阶段S1亚阶段环带黄铁矿核心S含量与理论值接近, Fe含量具弱亏损的特点；环带黄铁矿外环S、Fe具有弱亏损的特点。沉积成岩期黄铁矿为草莓状,不含As和Sb,金含量低,平均为59×10-6；热液成矿期早阶段黄铁矿颗粒较粗(≥100μm),其As、Sb和Au含量较低, As、Au平均分别为0.205%和275×10-6；热液成矿期主阶段S1亚阶段环带黄铁矿粒度较细(<50μm,10~20μm为主),外环As和Au含量高,外环As含量为0.1961%~7.897%,平均为1.4668%；Au含量为40×10-6~905×10-6,平均为429×10-6；Sb含量为0.01%~0.035%,平均为0.0233%。S2亚阶段毒砂具有富硫亏砷等低温热液毒砂特征, Au含量为230×10-6~1400×10-6,平均为643×10-6；Sb含量为0.019%~0.50%,平均为0.087%。晚阶段辉锑矿Au含量较低,平均为237×10-6。Au含量从成岩沉积期一成矿早阶段一成矿主阶段一晚阶段呈低或不含→低→高→低的特点分布。金可能以类质同象形式(固溶体形式)存在于毒砂和黄铁矿晶格中。
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