*Manuscript Click here to view linked References The earliest high-fired glazed ceramics in China: the composition of the proto-porcelain from Zhejiang during the Shang and Zhou periods (c. 1700 – 221 BC) Min Yina,*, Thilo Rehrena,§ and Jianming Zhengb a UCL Institute of Archaeology, 31-34 Gordon Square, London, WC1H 0PY, UK b Zhejiang Provincial Institute of Archaeology, Hangzhou, 310014, China * Corresponding author § New address: UCL-Q, Doha, Qatar Postal Address: UCL Institute of Archaeology, 31-34 Gordon Square, London, WC1H 0PY, UK Email address:
[email protected] Abstract Bodies and glazes of 54 proto-porcelain sherds and 18 non proto-porcelain samples from Shang and Zhou periods production sites in Deqing, Zhejiang province were analysed by EPMA-WDS. The results indicate that the bodies of all samples were made from local raw material – porcelain stone, with the proto-porcelain samples being made from clay of higher quality. Wood ashes, high in lime and low in potash, were intentionally applied to the proto-porcelain samples, resulting in the formation of lime-rich glazes whose composition were determined by a temperature-controlled mechanism. In contrast, kiln fragments and furniture show a potash-rich fuel vapour glaze, which formed unintentionally during use of the kiln. The firing temperature for most of the proto-porcelain glazes is around the maturing temperature for typical more recent lime glazes, showing that the potters were already at such an early time able to attain sufficiently high temperature in their kilns. Keywords proto-porcelain, Shang and Zhou periods, Zhejiang, China, porcelain stone, glazing technique, firing temperature 1.