Aegis

Aegis was the shield that Athena used. It had the face of the gorgon Medusa on it.

Aegis Media

The aegis on the Lemnian Athena of Phidias, represented by a cast at the Pushkin Museum
Alexander Mosaic (detail), House of the Faun, Pompeii
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.

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