是从非洲来的，I am serious.

The origin of the ores or metals use for Shang and other early chinese bronze is a current (2018) topic of research. As with other early civilisations (Egypt, Mesopotamia, Indus) the Shang period development was centered on river valleys, and driven in part by the introduction of intensive agriculture - in China such areas lacked ore deposits and required the import of metallurgical material. Typical Shang period bronzes contain over 2% lead, unlike contemporary coppers of the Eurasian Steppe. Analysis of the ore/metals origins has been based on lead content and trace isotope analysis.^[7] In the case of Shang period bronzes, various sites, from early to late Shang period, numerous samples of the bronze alloy are characterized by high radiogenic Lead isotope content (derived from both uranium and thorium decay), unlike most known native Chinese lead ores. Potential speculative sources of the ore include Qinling, middle to lower Yangtze area, and south-west china; the possibility that ore or metal was imported from Africa in this period has been proposed, based on potential isotopic matches, but challenged and rejected by other researchers. Pre-Shang (Erlitou culture) bronzes do not contain the radiogenic lead isotopes.^[7]

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• not convincing ! -弓尒- ♂ (199 bytes) () 01/09/2020 postreply 21:04:15