Lead isotopic study of Shang Dynasty bronzes (13-11 B.C.)and their ore sources

摘要

The Shang Dynasty civilization in China is based on the development of the bronze techniques. A large amount of Shang Dynasty bronzes, excavated from Jiangxi, Hubei and Henan Provinces, have become a focus of world attention. However, the Shang Dynasty center was located at Zhenzhou and Anyang city areas, Henan Province, where no large copper ores have been found so far. Therefore, where did the huge ore material for casting the bronzes come from? It is an unsettled question paid attention by the archaeologists and scientists. 35 Shang Dynasty bronzes and 21 copper and lead ore materials aged in the Shang-Zhou Dynasty, the Spring-Autumn Period and the modern time, have been measured by the use of mass spectrometry. Based upon lead isotopic ratios, the ore material for casting the bronzes with the middle isotopic ratios of 207pb/2 06Pb ranged in 0.8～0.9 could come from the ancient copper mine of Tongling, Jiangxi Province and Tong Lushan, Hubei Province and that with the high isotopic ratios (>0.9) could be from the northern part of the Shang Empire, called "Gongfang" in the historical records, e.g. today's Hebei and Liaoning Provinces. The others with the low isotopic ratios (< 0.8) might originate from polymetalic deposits, with the high isotopic ratios of 238U/204Pb in the ore flux or in the magma.