敦煌西土沟遗址冶金遗物研究

摘要

54 samples of 18 slags,9 ores,and 27 metal prills from an area of the Xitugou Site at Dunhuang in Gansu Province were analyzed by SEM-EDS.Most of the slags were produced from the smelting of pure oxi-dized copper minerals while a few are from the smelting of alloys containing arsenic;small amounts of pure oxi-dized copper and turquoise were found.The metal prills proved to be of various chemical compositions includ-ing Cu,Cu-As,Cu-Sn,Cu-Pb-Sn,Sn-Pb and more;Ag,Bi,Sb,Pb and SnO2were found widely in many of the prills.Calcium arsenite was found in one slag sample and arsenic trioxide was found in one prill.The analysis results indicate that the site once utilized a process to first smelt pure oxidized copper ore into copper and then add minerals containing elements such as arsenic and tin to produce alloys. One carbon sample unearthed to-gether with slags in area 2 of the site has been dated to 1890—1690BC(BP 3470±35 by AMS within 95.4%probability by OxCal v3.10).%对甘肃敦煌西土沟遗址7个地点的18个炉渣、9个矿石、27个金属颗粒共计54个样品进行了扫描电镜观测.认定大部分炉渣是氧化矿石直接冶炼红铜的,少量炉渣是冶炼含砷合金的;仅检测到含有少量硫化矿物的铜氧化矿石和绿松石;金属颗粒则具有红铜、砷铜、锡铜、锑铜(砷)、铅锡铜、锡铅铜(砷)、锡铅(铜)等多种成分组合.在一个炉渣样品中发现有砷酸钙,在一个金属颗粒中发现有砷氧化物.金属颗粒多次发现有银、铋、锑及锡氧化物.基于上述发现,对西土沟遗址的冶炼技术进行了推断,认为该遗址主要使用铜氧化矿石冶炼红铜,再配以含砷、锡等合金元素的矿料进一步冶炼获得各种合金.在第2地点与炉渣共出的木炭的碳十四年代测定结果为3470±35BP,OxCal v3.10校正为1890-1690BC (95.4%).