Aigis

The Aigis is the cloak (or brestplate) made by Athena from Medusa's head. It produced a sound as from a myriad roaring dragons and was worn by Athena in battle. The Aigis is of great value, ageless and immortal: a hundred tassels of pure gold hang fluttering from it, each of them tightly woven, and each the worth of a hundred oxen. It is a fearsome thing with a surface of gold like scaly snakeskin and linked serpents with the gorgon herself upon the goddess's chest—a severed head rolling its eyes, the gorgoneion.