NORTHERN SONG-JIN DYNASTY (AD 960-1234)

Of all the ceramic forms produced at the Jun kilns, the ‘bubble’ bowl perhaps shows the famous Jun glaze to its best advantage. The name is derived from the illusion of a soapy bubble that appears on the interior when viewed from a certain vantage. The instantly-recognizable opalescent blue of the Jun glaze is in fact primarily due to an optical effect, rather than to an actual blue element within the composition of the glaze. After high firing, the pieces in the kilns were cooled very slowly, resulting in the development of tiny globules of lime-rich glass within the silica-rich glaze matrix, a process known as ‘liquid-liquid phase separation’.

A comparable Jun ‘bubble’ bowl is illustrated by R. Krahl in Chinese Ceramics from the Meiyintang Collection, vol. 1, London, 1994, pp. 220-21, no. 388. Another example with vibrant purple-splash decoration, from the Linyushanren Collection, was sold at Christie’s Hong Kong, 2 December 2015, lot 2808.