Aegis
Aegis was the shield that Athena used. It had the face of the gorgon Medusa on it.
Aegis Media
The aegis on the so-called Athena Lemnia, a Roman statue type often identified as a copy of a work by the Classical Greek sculptor Pheidias (Dresden Skulpturensammlung)
First century BC depiction of Alexander wearing the aegis on the Alexander Mosaic, Pompeii (Naples National Archaeological Museum)
Augustus shown with an aegis thrown over his shoulder as a divine attribute in the Blacas Cameo; the hole for the head appears at the point of his shoulder.