The depiction of ducks in a lotus pond as a decorative motif on ceramics has its origins in the Tang dynasty and gained particular popularity in the Yuan dynasty on blue and white dishes and vases. The popularity of the motif continued throughout the Ming and Qing dynasties and featured prominently on ceramics from the Xuande and Chenghua periods, the late Ming period and the latter half of the Qing dynasty. The pair of ducks is associated with fidelity and harmony. In Designs as Signs: Decoration and Chinese Ceramics, Percival David Foundation, London, 2001, Stacey Pierson explains that pairs of mandarin ducks, yuan yang, represent marital fidelity or harmony as these ducks are said to mate for life. In association with lotus (homophonous with the word for harmony he), they can represent a wish for sons.