- 责任者：Zheng Bo (Key Laboratory of Orogenic Belts and Crustal Evolution ; Ministry of Education ; School of Earth and Space Sciences ; Peking University ; Beijing 100871 ; China) ; Zhang Jinguo
- 刊名：Mineral Deposits
- 出版年：2013
- 卷期：32(6)
- 关键词：金矿 ; gold ores ; 新疆 ; Xinjiang
- 页码：p.1117-1138
- 图表：13 illus., 2 tables, 24 refs.
- 分类号：1001
- issnNo：ISSN0258-7106
- isbnNo：CN11-1965/P
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The L7 vein in No. 4 ore district of the Baogutu gold deposit is composed of stibnite quartz-type ore body and native arsenic quartz-type ore body and contains some rare minerals, such as paakkonenite （Sb2AsS2）, native arsenic, native antimony, aurostibite and Au3Ag4Sb10S12. Based on petrographic observation, the authors identified five ore-forming hydrothermal stages. Pyrite -arsenopyrite stage （Ⅰ） consisted of massive arsenopyrites and pyrites with intense silicification. Coarse quartz stage （Ⅱ） formed comb or coarse quartz along the host rock and breccias. Au-As-Sb mineralization stage （Ⅲ） was composed of stibnite, native antimony, native arsenic, paakkonenite, electrum, native gold, aurostibite, Au3Ag4Sb10S12, miargyrite, tetrahedrite, lollingite, chalcostibite and quartz. Late Sb mineralization stage （Ⅳ） formed stibnite associated with calcite, native antimony and paakkonenite. Calcite stage （Ⅴ） formed only a few calcite （-quartz） veins, which ended the hydrothermal activity. The ore-forming fluid of stage Ⅲ greatly reformed the earlier-formed minerals, with arsenopyrite replaced by stibnite and lollingite, and stibnite by native gold, aurostibite, paakkonenite and native arsenic. The crystallization of stibnite was controlled by temperature and the quantity of reduced S species, while native antimony and native arsenic by fO2 and temperature. Arsenic and antimony were deposited as native arsenic, native antimony and stibnite, which consumed H2S. The open space also caused the escape of H2S. The loss of H2S destabilized the Au-sulfide complexes and finally caused gold deposition.