云南大理黄矿厂遗址银铅冶炼技术研究

Lead and silver production at Huangkuangchang site in Dali, Yunnan

云南大理黄矿厂遗址是一处明清时期大型银铅生产遗址。在以往研究中,已有学者对该遗址的开采年代、银课总额进行了梳理,但在冶炼技术复原方面还需进一步的研究。本研究通过分析黄矿厂遗址四个地点冶炼的炉渣,对黄矿厂遗址银铅冶炼技术进行了重建。研究结果显示,黄矿厂遗址各地点炉渣可依据其形态特征、主微量元素、稀土元素配分曲线以及铅同位素比值的差异分为A、B、C、D四类。A、B、C类炉渣使用焙烧还原熔炼法,D类炉渣则使用铁还原沉淀熔炼法进行冶炼。铅同位素测试结果显示B、C类炉渣所用矿石的铅同位素特征近似,D类炉渣则具有明显偏高的铅同位素比值。稀土元素的分析结果显示B类炉渣的δEu呈负异常,而其他三类均为轻微正异常。A类炉渣中一件含有高放铅,其余为与B、C类近似的普通铅,微量元素含量较为离散,分布范围远大于其他各类,显示了较为多元的银铅矿物来源。综上,黄矿厂遗址工匠可能使用了多种不同工艺进行冶炼,所用铅矿物可能来自多个不同矿床,显示该遗址在较长的生产周期中发生了多次生产技术与资源的变迁。

Huangkuangchang site in Dali,Yunnan Province is a large lead and silver production site of the Ming and Qing Dynasties.In previous studies,the mining age and total amount of silver tax at the site have been discussed,but further research is needed on the smelting technology used.This study reconstructed the lead and silver smelting technology of Huangkuangchang site by analyzing the smelting slags at four locations of this site.The results show that the slags from the various locations at Huangkuangchang site can be categorized into four groups—A,B,C and D,based on the differences in their morphological characteristics,major and trace elements,rare-earth element partition curves,and lead isotopic ratios.A,B and C slags were smelted using roasting-smelting,while the D slag was smelted using the iron reduction process.The lead isotopic analysis results show similar lead isotopic signatures for the ores corresponding to B and C slags,while the D slag has significantly higher lead isotope ratios.The analysis results of rare earth elements show thatδEu of the B slag is negatively anomalous,while those of the other groups are slightly positively anomalous.For the A slag,one piece contains highly radioactive lead but the rest are similar to B and C slags,and the trace element content is more discrete while the distribution range is much larger than those of other groups,showing a more diversified source of silver-lead minerals.In summary,workers at Huangkuangchang site may have used a variety of processes for smelting,and lead minerals used may have come from a variety of different deposits,suggesting that the site underwent a number of changes in production techniques and resources over its long production period.