The ancient city of Plotinopolis lies on Aghia Petra hill which rises gently above the plain south of Didymoteicho (Thrace), not far from the Hebros river. Little information on the city, which was renamed by Trajan, has come down to us, although it features on ancient route maps and was mentioned by Ptolemy (3.11.3) and Procopius (Aed. 4.11.19).1 Few archaeological excavations have been carried out, and of the city itself few vestiges remain (fig. 1). In 1965, while the Greek army was excavating a trench at Didymoteicho, a gold bust of an emperor wearing a cuirass came to light.2 There is no documentation on its discovery, no report on the Greek army’s intervention, nor even any information on the follow-up excavation carried out by A. Vavritsas.3 Having initially been hidden by its discoverers, the bust narrowly escaped being melted down – the fate suffered by the majority of antiquities made of gold – for already in the days directly after the discovery one part of the edge of the cuirass was cut into pieces and sold off by the soldiers. This reckless action betrayed the bust’s discoverers and made it possible for the unit’s officers to recover the bust. Considering its extreme rarity, this type of object is important, not only for the questions it raises regard-ing its original purpose and dating, but also for our understanding of toreutics. Our interpretation of the piece, which is effectively without archaeological context, has to rely on a critical analysis of its technical, iconographic and artistic aspects, taking into account extant depictions of imperial busts and textual references.