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为了探讨含金毒砂的形成机理,作者进行了一些热液实验。实验中针状的富金条带状毒砂(金含量达1.7wt％)是在400—500℃和1×10~8—2×10~8Pa的水压条件下获得的。与产于LeChatelet矿床(法国Creuse地区)的似针状富金毒砂相比较,揭示出类似的As/S比值分带,有着相似的金含量和成带现象。后者的主矿物石英中的流体包裹体研究表明,含金毒砂形成于高温和可变化的氧化还原环境中。与邻近的Villeranges金矿床(其毒砂的形成温度大约为200℃,金主要被俘获于毒砂的结构中)相比表明,在此种结合中,温度似乎不可能是主要的影响因素。它表示非平衡的快速结晶可能导致在很宽的T-P-fo_2范围内金被捕获。在已知有金的地球化学异常而又不见明金的地区,强调了毒砂的似针状习性的实际重要性。
In order to explore the formation mechanism of arsenite containing gold, the author conducted some hydrothermal experiments. The acicular gold-rich strip-shaped arsenopyrite (gold content of 1.7 wt%) was obtained under the conditions of 400-500 ℃ and water pressure of 1 × 10-8-2 × 10-8Pa. Compared with the acacia-like arsenic produced in the Le Chatelet deposit (Creuse area, France), a similar banding of As / S ratios is revealed with similar gold content and banding. Fluid inclusions in the latter, the main mineral quartz, have shown that gold-bearing arsenites are formed in high temperature and a variable redox environment. Compared with the adjacent Villeranges gold deposit, where the formation temperature of arsenopyrite is about 200 ° C, the structure of the gold that is primarily captured in arsenopyrite shows that temperature seems unlikely to be a major contributor in this combination. It shows that unbalanced rapid crystallization can lead to gold being trapped over a wide range of T-P-fo_2. In areas known to have geochemical anomalies of gold that are not visible, the actual importance of needle-like habit of arsenopyrite has been highlighted.