yan, type of ancient Chinese bronze steamer, or cooking vessel, used particularly for grain. It consisted of a deep upper bowl with a pierced bottom, which was placed upon or attached to a lower, legged vessel similar in shape to the li. It was produced during the Shang, or Yin (18th–12th century bc), and Zhou (1111–256/255 bc) dynasties.
Pottery yan first appeared during the so-called Longshan culture (c. 3000–2000 bc, during the Neolithic Period), but the form became popular during the Shang dynasty and the early Zhou dynasties. The bronze yan of the early Shang dynasty was used as a ritual utensil. It often had two handles at the rim of the mouth; these were sometimes marked with inscriptions or cast patterns. Bronze yan of the Western Zhou dynasty and the Spring and Autumn period were usually square in shape, while those from the Warring States period were generally round. The yan was not usually elaborately decorated. It was increasingly rare after the later Zhou dynasty.