The extraordinary effect of this glaze is achieved by applying an opaque stippled turquoise glaze coloured with copper and made opaque by mixing the arsenic as an opacifier. Rose Kerr noted in Chinese Ceramics, Porcelain of the Qing dynasty, London, 1986, p. 88, that while visual examination reveals there to be two distinctive types of robin's-egg glaze, one streaked with copper-red and the other stippled with blotches of turquoise and dark blue, further analysis is required to clarify the chemistry of these glazes.

The peacock-feather glaze appears to be closely related to the more common robin's-egg glaze, but the former is much rarer, possibly due to the difficulty in successfully achieving its desired effect. A near identical, although slightly larger, Yongzheng-marked censer was sold at Christie's Hong Kong, 1 November 2004, lot 876; and another from the Edward T. Chow Collection sold at Sotheby's Hong Kong, 19 May 1991, lot 502.

Compare also with several other peacock-glazed vessels in important collections, such as the Yongzheng-marked zun from the J.M. Hu and C.P. Lin collections, illustrated by R. E. Scott, Elegant Form and Harmonious Decoration, Percival David Foundation of Chinese Art, and Sun Tree Publishing Ltd., Singapore and London, 1992, pl. 151; a Qianlong jar of 'fish basket' form is illustrated in Kangxi Yongzheng Qianlong, Qing Porcelain from the Palace Museum Collection, Forbidden City Publishing House, Hong Kong, 1989, p. 457, no. 139; and a moonflask with this glaze is illustrated in An Exhibition of Important Chinese Ceramics from the Robert Chang Collection, Christie's London, 1993, no. 48, sold at Christie's Hong Kong, 28 November 2006, lot 1305.