Athena placed Medusa’s severed head on her protective aegis in Greek mythology.
After Perseus killed Medusa, he gave the Gorgon’s head to Athena. The goddess mounted it on her aegis, a divine protective garment or shield traditionally associated with her. The head retained its petrifying power, so its image became a formidable emblem of protection.
The aegis is sometimes described as a shield and sometimes as a breastplate or animal skin, depending on the artistic and literary tradition. In Greek art, the Gorgon face placed on it is called a gorgoneion.
This story helps explain why Gorgon faces appeared on ancient Greek armor, pottery, buildings, and coins. The image was frightening but also protective: it was meant to repel danger rather than merely decorate an object.