Paired mandarin ducks symbolize conjugal fidelity. Paired mandarin ducks standing on lotus blossoms symbolize divine chastity in Buddhist imagery.
The present example is particularly unusual for the addition of blue glaze. Compare a sancai-glazed pillow of similar design illustrated in The Panoramic Views of Chinese Patterns, Heibonsha, 1985, fig. 202, and another exhibited in To So mei to ten (Exhibition of Fine Tang and Song Ceramics), Shirakiya, Tokyo, 10 - 22 April, 1964, fig. 30.