山东新城金矿黄铁矿标型特征及含金分析

Typomorphic Characteristics and Gold-bearing Analysis of Pyrite in Xinchen Gold Deposit in Shandong Province

山东新城金矿位于华北板块胶北隆起内,矿床成因主要为构造热液蚀变,焦家断裂为其主要控矿构造。矿床类型为破碎带蚀变岩型金矿。据成矿物质的生成时序、共生组合,将成矿阶段划分为含金石英菱铁矿黄铁矿阶段(Ⅰ)、含石英多金属硫化物阶段(Ⅱ)、石英-黄铁矿阶段(Ⅲ)、石英-方解石阶段(Ⅳ)4个成矿阶段和5个成矿世代。黄铁矿的标型特征与金矿的含金性密切相关,不同成矿阶段和成矿世代的黄铁矿标型特征是不同的。以不同成矿阶段和成矿世代的黄铁矿的标型特征为研究对象,通过黄铁矿的形态特征研究,认为晶形差的黄铁矿比晶形好的黄铁矿含金性好。晶形为五角十二面体的黄铁矿比晶形为立方体的黄铁矿含金性好。通过黄铁矿的物性特征研究,认为铜黄—暗黄色的黄铁矿相对浅黄—亮黄色的黄铁矿含金性好。通过黄铁矿的结构特征研究,认为细粒结构的黄铁矿比粗粒结构的黄铁矿含金性好。通过黄铁矿的成分特征研究,认为发生类质同象替代的黄铁矿比不发生类质同象替代的含金性好。

Xincheng gold deposit in Shandong is located in Jiaobei uplift of the North China plate. The origin of the deposit is hydrothermal alteration, and Jiaojia fault is the main ore - controlling structure. It is crushed zone alteration type,gold deposit. According to the timing of mineralization, the metallogenic stage is divided into four metallogenic stages and five metallogenic ages, such as gold - bearing quartz siderite pyrite stage （ Ⅰ ）, quartz - polymetallic sulfide stage （Ⅱ）, quartz - pyrite stage （Ⅲ） and Quartz - calcite stage （Ⅳ）. The typomorphic characteristics of pyrite are closely related to the gold content. The pyrite typomorphic characteristics are different in different metallogenic stages and metallogenic ages. Regarding typomorphic characteristics of pyrite from different metallogenic stages and metallogenic ages as the study object, through study on morphological characteristics, it is regarded that pyrite with poor crystal form has better gold content than pyrite with better crystal form. Pyrite with pentagonal dodecahedron has better gold than pyrite with cube shape. The dark yellow pyrite has better gold than the bright yellow pyrite. The pyrite structure of fine - grained structure has better gold than that of coarse - grained pyrite. Pyrite substitution for isomorphism has better gold than no substitute for isomorphism.