A tiny object with outsized significance has come up from the sea floor off Egypt. A bronze signet ring engraved with the Lighthouse of Alexandria has been recovered from the submerged Royal Island of Antirhodos, once part of the royal quarters of Alexandria's Portus Magnus. The find was made by the European Institute for Underwater Archaeology, directed by Franck Goddio, working with Egypt's ministry of tourism and antiquities and supported by the Hilti Foundation. It is the only ring of its kind known to exist — the first time the lighthouse, one of the seven wonders of the ancient world, has been found engraved on a seal ring. The engraving matches depictions of the lighthouse on Alexandrian coins dating to the second century AD. The context matters as much as the object. The ring was excavated in the legendary palace of Antirhodos, a center of power visited by the geographer Strabo between 29 and 25 BC. Its presence there suggests the palace once housed administrative offices, including ones overseeing the famous lighthouse — a working seal for official impressions pressed into wax or clay. Specialists welcomed the find with measured enthusiasm. One maritime archaeologist called it an interesting and important discovery, while noting that its full significance will depend on a detailed account of exactly where it was found and whether it sat in a datable context. The ring emerged from a field season covering four points of interest in the Eastern Harbour, including the Temple of Isis and the so-called Palace of Antony. Egypt's minister of tourism and antiquities inspected the excavation, which also yielded pottery and glass spanning the fourth century BC to the fourth century AD. Specialists called the ring an important discovery, while noting that a detailed account of its exact findspot and datable context will determine its full significance.