This is the oldest known sculpture of a Gorgon, from the Temple of Artemis in Corfu, Greece. It was created around the 4th Century [500-599 CE], and shows most of the classic features for a Gorgon... round face, staring eyes, snakes in hair, lolling toungue. The figure almost certainly once had wings, as well as tusks coming from the mouth, but these have been lost to time. There is also an nidication that this is specifically the Gorgon named Medusa for one simple reason... the sculpture also shows her two children, Pegasus the winged horse (to her left), and Chrysaor the 'warrior with a golden sword' (to her right).
This copy of the image comes from the Wikipedia website [Link Here].