Upon hearing of the royal engagement, Hephaestus presented Harmonia with an exquisite necklace and robe as a wedding gift.
Although no solid description of the Necklace exists, it is usually described in ancient Greek passages as being of beautifully wrought gold, in the shape of two serpents whose open mouths formed a clasp, and inlaid with various jewels.
This led to Semele's destruction when she foolishly demanded that Zeus prove his identity by displaying himself in all his glory as the lord of heaven.
Amphoterus and Acarnan dedicated the Necklace to the Temple of Athena at Delphi, to prevent further disaster amongst human wearers.
The tyrant Phayllus, one of the Phocian leaders in the Third Sacred War (356 BC-346 BC), stole the necklace from the Temple and offered it to his mistress.
After she had worn it for a time, her son was seized with madness and set fire to the house, where she perished in the flames along with all her worldly treasures.