Porphyry basin 2nd-3rd century A.D. Roman Stone basins such as this served as bathing tubs in one or another of the large imperial baths with which Rome was furnished. This example, although undecorated, provides a good impression of the richness and extravagance ofimperial patronage. Porphyry was regarded as a stone that had special associations with the emperor, because of its purple color and also because of the great expense of quarrying, transporting, and carving it. Most of the surviving Roman porphyry tubs are to be found in Rome, where they were reused later as sarcophagi in early Christian times.. Porphyry basin. Roman. 2nd-3rd century A.D.. Porphyry. Imperial. Stone Sculpture