The work came to light in 1846 about 80 cm below the ground near via San Primo in Milan: the discovery at a shallow depth and in the circuit of the fortifications allows the hypothesis that it was used as a construction material for the walls. . The sculpture features the effigy of a mature woman with a physiognomy characterized by high cheekbones, huge wide eyes, and a perfect face shape. The garment is richly adorned with a high ribbed bonnet decorated with a pearl diadem with an oval gem in the center. The high quality of this portrait, which makes it one of the most significant examples of Byzantine art in the West, raises the problem of its identification. Variously interpreted as the empress Theodora (517-584), wife of Justinian, or as Justina, mother of the Western emperor Valentinian II, the work is placed in balance between impersonal evocation of majesty and naturalism, thanks to the association between the individualized rendering of the physiognomic features and an essential treatment of the volumes.