The gold Ampulla is used to hold the consecrated oil with which a sovereign is anointed during the coronation ceremony. It is cast in the form of an eagle with outspread wings. The head of the eagle is removable, and there is an opening in the beak for pouring the oil.

The design is based on an earlier, smaller vessel, which was based on a fourteenth-century legend: the Virgin Mary is said to have appeared to St Thomas Becket and presented him with a golden eagle and a vial of oil for anointing future kings of England. Oil from the Ampulla is poured onto the twelfth-century Anointing Spoon (RCIN 31733) at the most sacred moment of the coronation. The gesture of anointing, when the Archbishop touches holy oil onto the head, breast and hands of the sovereign, dates back to the Old Testament Book of Kings, where the anointing of Solomon as King is described.