Research On Copper And Iron Smelting Technology In Central Yunnan In Ming And Qing Dynasties

During the Ming and Qing Dynasties,Yunnan was a major copper-producing region,and the development of the copper and iron metallurgical technology reached its peak.Most of the researches on the copper metallurgical techniques in the academic circle focuses on the interpretation of ancient documents,and few scholars have discussed the metallurgical relics of the copper and iron metallurgical sites in central Yunnan.Therefore,this study will play a positive role in revealing the copper and iron rmetallurgical techniques in central Yunnan.By the investigation and analysis of the sites of Mobuchang in Mile,the sites of Lengshuigou in Lufeng,and the sites of Muche in Huaning,the sites of Sanjiachang in Yimen,the sites of Shangtiesuo in Jinning,combined with the literature records,it is concluded that the site of Shangtiesuo had been mined and smelted during the Yuan Dynasty,and the other four sites could be traced back to the Ming and Qing.The methods such as literature survey,field investigation and experiment analysis were applied to this research.The slags discovered at the five sites were mainly examined and analyzed by scanning electron microscope(SEM),which preliminarily revealed the copper and iron metallurgical technology of these five sites.The experimental results show that there were three styles of copper smelting techniques:Smelting oxide ores to copper;Dead roasting and smelting sulphide ores to copper;Roasting and smelting sulphide ores first to matte and then to copper,including the sites of Mobuchang,Lengshuigou,Muche,and Sanjiachang.The third style was very adept at enriching smelting operations and was able to discharge different grades of matte-slags.By comparing the Shangtiesuo site with other iron smelting sites in terms of slag matrix composition,iron-silica ratio,alkalinity,etc.,combined with the slag composition and physical analysis,it is concluded that the site is a block iron smelting site.The silicic acidity,alkalinity and density of slags basically meet the requirements of the modern metallurgical theory for the physical and chemical properties of the slag.The development of the mining and metallurgical industry in central Yunnan has had a huge impact on the local society,economy and culture,which is mainly manifested in:promoting the development of the urban economy,facilitating the further integration of the Han and ethnic minorities,improving the traffic conditions in the mountainous areas,and forming a unique mining and metallurgical culture in Yunnan.At the same time,while central Yunnan was prospering,it also caused great damage to the local ecological environment.