How was a you vessel used in ancient Chinese rituals?

In ancient Chinese rituals during the Shang and early Zhou periods, the you was a specialized bronze vessel used for wine. It functioned as a container for sacrificial offerings, which were presented primarily to the spirits of clan ancestors, including those of the ruler and his family.12

These vessels were typically kept in the ancestral hall of the clan, though some were buried with their owners. While many bronze vessels were created for use in temple sacrifices, others—often those that were poorly cast or inscribed with the names of the deceased—were specifically intended for placement in tombs. By the early Zhou dynasty, inscriptions on such vessels often included the phrase "May sons and grandsons forever treasure and use it," further highlighting their central role in ongoing ancestral veneration.2