Page 98 - The colours of each piece: production and consumption of Chinese enamelled porcelain, c.1728-c.1780

CHAPTER 2 The Production of Enamelled Porcelain and Knowledge Transfer

indicates that except for the new colours received from the Imperial workshop, the

manufacturer at Jingdezhen at the time conducted many experiments in enamel

colours itself.

More importantly, it shows that Jingdezhen not only accepted new enamel colours,

but also innovated according to its own technological circumstances. Scientific

research has shown that the glass base for Jingdezhen enamel colours was lead-

potassium-silicate formulation, while the composition of the enamelled porcelain

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made at the Imperial workshop was lead – borate – silicon. Zhang Fukang of the

Shanghai Silicate Institute has carried out a comparative analysis of samples of Palace

workshop falangcai (imperial workshop enamelled porcelain) and Jingdezhen

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enamels. He has noted that there is a difference in the flux formula. Jingdezhen
consisted of Lead oxide - Potassium oxide (PbO -K2O) whereas falangcai also has

boric oxide. These oxides act as flux that lowers the melting temperature of the

enamels. It has also been shown that the new enamels of Jingdezhen were similar in

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formula to its own technique of wucai colours.

Recently, another scientific examination has confirmed the point that Jingdezhen

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has constantly improved on recipes of enamels, as well as the application methods.

Four enamelled porcelains were examined, one made by the imperial workshop

(dating from the late 1720s) and three made in Jingdezhen (dating from the late 1720s

to the early 1730s). An analysis was carried out by using optical microscopy and non-

54 Zhang Fukang, ‘Zhongguo chuantong diwen seliao yu yangcai [Chinese Traditional Low Fired
Glazes and Over-glaze Colours] in Zhongguo gudai taoci kexue jishu chengjiu [The Achievements
of Chinese Pottery] (Shanghai, 1986), pp.333-48.
55 Ibid.
56 This was conducted by Wang Zhuping from the National Palace Museum, ‘Cong hexue
wenxian fenxi huigu kan falangcai, yangcai yu fencai de mingming ‘[Scientific Analysis of
Chinese enamelled porcelain and its terms’, Gugong xueshu jikan [Research Quarterly of the
National Palace Museum], 29, 3(2012), pp.138-140.
57 Ibid.
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