In addition to a collection of Pb isotopic signatures, these databases provide informed geochemical information. Such databases already exist in Europe, and North and South America, and have been shown to be indispensable in provenance studies. Despite this increase however, no attempt has been made to create a centralized database of assessed Pb isotope analyses for archaeologically relevant Pb ores and other related metal deposits. As a result, Chinese archaeologists and historians have taken interest in Pb, resulting in an increased number of provenance studies with particular focus on the circulation of bronze metalwork dating to the Shang-Zhou period (ca. Throughout Chinese history, Pb was commonly used in a variety of materials and processes including bronzes, lead-barium (Pb-Ba) glasses, glazes, pigments, firearms, and in silver production. The relative abundances of these four isotopes impart age information and often a unique geochemical signature in ores, of which the latter is commonly the focal point in archaeological provenance studies. The abundance of primordial Pb remains unchanged while the concentrations of the other three increase over time due to the radioactive decay of their U and Th parent isotopes of 238U, 235U, and 232Th, respectively. Primordial Pb can therefore be leveraged to model the elapsed time since the initial formation of a given Pb-bearing mineral. Often cited in these debates, and the basis for the usefulness of Pb isotopes in provenance studies, lies in the relative abundances of four stable isotopes ( 204Pb, 206Pb, 207Pb, 208Pb), of which 204Pb is primordial and has no long-lived radioactive parent. Indeed, the approach has had a long and controversial history of proof of concept, setback, and eventual acceptance. In archaeology, the method of comparing the Pb isotopic “fingerprints” of artifacts and other materials to that of ores has been widely applied despite initial and ongoing debates regarding their application and overall validity. Lead (Pb) isotope geochemistry has played a vital role in tracing the fluid pathways and sources of metal in ore deposits, revealing chronological information of ore body formation, evaluating the economic potential of ore exploration, and in the provenancing of archaeological materials.
The isotope data themselves are presented in ternary diagrams that allow for their concise and accurate comparison. Using the isotope database, and supportive geological and archaeological background information, three case studies are presented that detail the provenancing of Chinese cultural materials. We pay particular attention to the geological settings of host ore deposits that were likely exploited in ancient and historic China, detailing the heterogeneity and homogeneity of their ore formation across different metallogenic provinces and belts. In this paper we have compiled and evaluated all currently available Pb isotope data for galena and K-feldspars in China, and provided geological interpretations for how their ore-forming substances evolved across relevant tectonic terrains. A well reasoned lead (Pb) isotope-driven provenance study lies in concert with a comprehensively evaluated database of geological ore sources and accompanying archaeological and contextual information.
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