The face on this piece is that of Minerva, who is the Roman goddess of wisdom, commerce, and magic among other things. She is the daughter of the titaness Metis and the god of the heavens, Jupiter. Although she is not seen with it on this item, Minerva is often depicted with her sacred creature, which is an owl. This owl is often called the owl of Minverva.
When you use this piece, the presence of the Owl of Minerva is what you are getting. The owl will fly from the heavens to give you the secrets that Minverva holds regarding her three strongest traits. These are wisdom, commerce and magic. The owl will give you the wisdom of the gods to know all things, the knowledge of commerce to bring you wealth, and the knowledge of all magic in order to be able to create your own spells, potions, enchantings, etc.