Max Pirkis plays the young Octavian so perfectly in Rome: soft-spoken, measured, as calculating as a little abacus, and yet (in a Roman way) kind-hearted, sort of. Except when truly backed against the wall (e.g., by the Gauls who abduct him and later Mark Antony), he almost always remains in control of his temper, and you could tell he felt bad afterward about what he and Pullo did to Niobe's brother-in-law.
In real life, he grows up to be Rome's first and greatest emperor, Caesar Augustus. One does question his parenting skills, considering the things his progeny got up to, but never mind: by Roman standards, he was the best they had.
This is the same image as before reconfigured as a shining globe. The purple chains are meant to resemble the wreath of laurels and the tessellated design might now be seen as carved jade. Did the Romans know about jade? On the DVD for the first series of the show, someone---the director or the writer---mentions that Caesar wore silks from China.
At any rate, these cyan-tinted stones with purple tones seemed right for young Octavian, bless him.