I believe the choice of Porphyry in the portrait group of tetrarchs speaks to imperial power. Portrait of the Four Tetrarchs is a porphyry sculpture group of four Roman Emperors dating from around 300 AD. The sculptural group has been fixed to a corner of the facade of St mark's Basilica in Vence, Italy since the Middle Ages.
Anti-bodies. This is not a hard question to answer, as you can just copy/paste the question into a search engine to get an adequate answer.
