Two baskets discovered in the course of German excavations in a private house of the Parthian period in Babylon contained many pearls and a number of small artefacts, mainly of semi-precious stones. Some of the objects in this 'treasure', which has been interpreted as a gem-cutter's stock of raw materials, may have come from the shrine of Marduk of Esagila. Of these, this divine seal is surely one of the most outstanding items. Carved in flat relief on the curved surface of the seal cylinder, which is drilled through lengthways, standing on a scale-like plinth is the weather god Adad, with feathered crown and with lightning bolts in hand. In his left hand he holds on a leash a two-headed mythical creature. On his richly decorated robe are round decorative discs with astral symbols. Three cuneiform inscriptions on the back of the costly seal refer to its changing ownership. First, a short Babylonian note declares that this is a seal of the god Adad; a later addition, on the other hand, identifies it as the property of the god Marduk from the possessions of the Temple of Esagila; and according to the Assyrian inscription the divine seal was dedicated as a votive offering to the god Marduk by King Esarhadon (680-669 BCE).