Perseus could not look at the Gorgon directly; he watched her in a polished shield, and so lived. This cuff keeps both halves of that story. One face is the Gorgon herself, amethyst crowned with silver serpents; turn it, and the other is the aegis — a pierced shield with a moonstone set where the mirror held her reflection. It is the only object in the archive made to be worn two ways: the gaze, and the guard against it. The wear inside the band suggests its keeper turned it often.