This vase is one of a group of oinochoai (jugs used for pouring wine) made of faience and decorated in high relief with portraits of the Ptolemaic queens of Egypt pouring a libation (liquid offering) at an altar. From the time of Ptolemy II onwards (284-246 BC), the rulers of Alexandria, at that time the capital of Egypt, were worshipped as deities in their own lifetimes. These jugs appear to have been made for their loyal subjects wishing to pour libations in their honour. The queens, who are named by inscriptions, are regularly shown with a cornucopia in one hand and a libation bowl in the other, standing between an altar and a sacred column. This particularly well-preserved jug bears the portrait of Queen Arsinoe III (221-203 BC), wife of Ptolemy IV.