Medusa head (gorgoneion) with wings in the wild hair and snakes around the face. This is an extremely common subject, especially in the late Roman period, presumably offering demonic protection for the wearer in the way the same subject does on a shield or aegis.

On the reverse of the cameo there is an engraved symbol resembling an inverted triangle, which may point to the stone having been used during the medieval period as a sign of the Trinity or indicating that it had a further amuletic function in combination with the Medusa.

The back is rough and broken having been cobbed out of the stone with a hammer.

Reverse of cameo: engraved symbol resembling an inverted triangle

Text adapted from Ancient and Modern Gems and Jewels in the Collection of Her Majesty The Queen, London, 2008