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讨论了秦岭卡林型金矿床中Ａｕ 、Ａｓ 的元素地球化学、矿物学特征。在含矿岩系中获得的Ａｕ、Ａｓ 等成矿元素初始含量较高，且主要集中在成岩黄铁矿中。在矿石样品中对含砷硫化物矿物的研究表明，Ａｕ 、Ａｓ 在矿物显微结构中具有强的正相关性。在大量金进入到硫化物结构之前，就已有［ＡｓＳ］３ － 的存在。在含砷硫化物矿物中，金多半以一种带电类型（Ａｕ３ ＋） 存在， 它很可能替代铁位置上的过剩砷， 以固溶体方式沉淀于硫化物矿物中。此时， 黄铁矿构成（Ａｕ３ ＋ ，Ｆｅ２ ＋）（［ＡｓＳ］３ － ［Ｓ２］２ － ），毒砂构成（Ａｕ３ ＋ ，Ｆｅ２ ＋）（［ＡｓＳ］３ － ［ＡｓＳ］３ －） 。通过电子探针（ＥＭＰ） 和透射电镜（ＴＥＭ） 对秦岭卡林型金矿含砷硫化物矿物中金的赋存状态的研究表明，在金的成矿作用早期阶段， 金主要以固溶体形式优先富集于含砷黄铁矿和毒砂及砷黝铜矿之中，并且认为是以金的氧化和砷的还原的共沉淀方式发生的。在此之后的金成矿作用晚期阶段，由于热液蚀变和结晶作用程度的增高，寄主矿物耐熔性质相对降低，加之金本身的聚集能力，和因过量砷加入而造成的含砷硫化物矿物的晶格缺陷，致使已形成的固溶体金以“出溶”形式发生再分布，赋存于硫化物矿物晶粒
The elemental geochemistry and mineralogical characteristics of Au and As in the Carlin-type gold deposits in Qinling are discussed. The initial contents of Au, As and other ore-forming elements obtained in the ore-bearing rock series are high, and are mainly concentrated in diagenetic pyrite. Studies on arsenic-sulfide minerals in ore samples show that Au and As have strong positive correlations in the mineral microstructure. The presence of [As] 3 - is already present before a large amount of gold enters the sulfide structure. In the arsenic-sulfide minerals, gold is mostly present as a charged species (Au3 +) and is likely to replace excess arsenic at the iron sites by precipitation as a solid solution in sulfide minerals. At this time, pyrite forms (Au3 +, Fe2 +) ([AsS] 3- [S2] 2-) and arsenopyrite forms (Au3 +, Fe2 +) ([AsS] 3- [AsS] 3-). Studies on the occurrence of gold in arsenic-sulfide minerals in Carlin-type gold deposits in Qinling by means of electron probe (EMP) and transmission electron microscopy (TEM) show that gold mainly takes the form of solid solution in the early stages of gold mineralization Enriched in arsenic-containing pyrite and arsenopyrite and arsenic-tetrahedrite, and is believed to occur by co-precipitation of gold oxidation and reduction of arsenic. In the later stage of gold mineralization, due to the hydrothermal alteration and the increase of the degree of crystallization, the refractory properties of the host minerals are relatively reduced, together with the gold’s own aggregation ability and the arsenic sulfide minerals caused by the excessive addition of arsenic Of the lattice defects, resulting in the formation of solid solution gold in the form of “redissolved” redistribution occurred in the sulfide mineral grains