Wanderers in that happy valley, Through two luminous windows, saw Spirits moving musically, To a lute's well-tuned law, Round about a throne where, sitting (Porphyrogene!) In state his glory well-befitting, The ruler of the realm was seen.
— from Edgar Allen Poe, The Haunted Palace
porphyrogenite n.
A Byzantine emperor's son born in the purple or porphyry room assigned to empresses, hence a prince born after his father's accession; a person born into the nobility.
Nice.
That’s a pretty stone, true porphyry comes from Mons Porphyrites in Egypt, and due to the natural dimensions of the deposit, the quarried stone is not of colossal size.
The tetrarchy sculpture:
https://upload.wikimedia.org/wikipedia/commons/6/67/Venice_%E2%80%93_The_Tetrarchs_03.jpg
