Qin Early Bronzes Technology Archaeological Research

After a long time of development, the kingdom of Qin gradually grew powerful and became formidable. Finally it established the first centralized authority empire after unifying six kingdoms into one united state by war in Chinese history. During such a process, the effort and contribution of early Qin people can never be overstated, accordingly, the research and study of early Qin culture stands out as one of the focal issues in the field of archeological and historical study.The bronze, especially the bronze weapons in early Qin period are indispensable elements of Qin people, they not only reveal the achievement of bronze casting technology, but also reflect problems of the military affairs, politics, economy and culture in early Qin period. This dissertation focuses on the study of a group of weapons in early Qin period with some technological approaches. It tries to explore the characteristics of their manufacture technology and raw mineral materials by studying their metallographic structures, ratios of alloy elements and lead isotope ratios, thus to provide important reference to the study of early Qin culture.The range of action of early Qin people mainly locates in areas as West Dog Hill (Xichui), Qin, Qian, the confluence of Qian and Wei, Pingyang, Yong, and so on. where is the place the early Qin culture originated and developed. This dissertation is based on the study of bronzes evacuated from places of Longnan area in east Gansu Province, Tianshui, Changlong area and Baoji area in the west part of Shaanxi Province. By studying bronze wares from these areas, it can adequately reveal the characteristics contained in them about the early Qin bronze culture.The ratios of the bronze alloy elements reveal:1) The Sn content in the bronze weapons is 10～18%, the Pb content is 2.12～9.83%. The metallographic structure is of casting state, and it is similar to that of other kingdoms. The results show that the early Qin people have already mastered the key casting technology to make bronze weapon; 2) The bronze architectural components evacuated in Fengxiang have a bronze content of 73～83%, the Sn content of 10～18%, the Pb content of 1～10%, which are alloys of lead, tin and copper. This shows that the early Qin people have already realized that the bronze with 10～18% Sn content has the best hardness and tensile strength.Trace element analyses to the bronzes evacuated in the four areas show that there are no significant differences regarding the trace elements, which means the bronzes excavated from Longxian, Lixian, Fengxiang and Baoji are made out of the same copper mines. Above of all, it further illustrates that the early Qin bronze culture exploited the same copper mines from West Zhou Dynasty to East Zhou Dynasty. That is say, there is continuity in them.Lead isotope ratio relationship charts show:the samples of the four areas have overlapping area, which covers samples from Baoji. Some Longxian samples distribute under the overlapping area, and some samples from Lixian extend above the overlapping area, which shows that the two share not only the same lead mines, but also use lead mines from different areas. Especially, lead isotope ratio ranges of Fengxiang samples cover that of the samples from the other areas which indicates that Fengxiang was already the political and economic center of Qin people as early as the Spring and Autumn Period.The result of the research reveals that the bronze smelting and casting profession of early Qin people has already been quite advanced, it is pretty likely that they had exploited the rich lead mine and copper mine resources in east Gansu Province of Qinling Mountain. They might have had independent mining, metallurgy and bronze manufacturing profession, and also had mastered the advanced bronze smelting and casting technology, especially including bronze weapons. This conclusion shows that the Qin people master the bronze casting technique during West Zhou and East Zhou period. It has great archeological significance, because the potential information post out that the early Qin people could expand gradually from west to east just depending on the guarantee of mineral resource and advanced techniques.The Raman spectrum analysis shows that the inclusion in the bronze are lead carbonate (PbCO3), Lead (Ⅱ) oxide (PbO), Cuprite(Cu2O) and Carbon(C). PbCO3 and PbO are important carbonate and oxide of lead, which indicates the corrosive process of lead as Pb→PbO→PbCO3. The Raman Analysis demonstrates that the round dark grey inclusion in the metallographic structures is Cu2O, possibly the result of casting or later corrosion.In addition, the dissertation chooses the early Qin bronze as research object through modern Instrumental Analysis to give them a systematical study, which is a new research at home and abroad. On the other hand, it introduces the laser ablation plasma mass spectrometer to study bronzes about their trace elements in situ with non-destructiveness. Meanwhile, Micro-Raman spectroscopy is employed to study the inclusion in metallographic texture. These attempts can be beneficial to promote the researching methods about ancient bronze explore.Finally, due to the limitation of my personal ability, the limited amount of samples and the inadequacy of literature, some of the relevant issues are short of sufficient further probe, especially about the mining sources of the mine materials in early Qin period, this would be the focus of further study for the next step. It is of my hope that the dissertation can draw more people to provide valuable suggestions, and attract more people to the study of early Qin culture.