A new Sestertius of Nero

I won this in the CNG auction that ended today. To me (your opinion may vary) if you wanted one single coin to represent the Roman Empire you would want a Sestertius of Nero. They were large, their size gave the engravers room to showcase their talents in a way that smaller coins did not and how can you not just be impressed by a big hunk of bronze from one of the most evil rulers in history?

When I post these things I usually give a brief history of the emperor and his time, but I think most of us know at least some details from Nero's life. He became Emperor inn AD 54 when his mother murdered his step father Claudius Caesar, he murdered his step brother Britannicus because "A second Caesar is a Caesar too many." He went on to kill his mother in AD 59, all of this killing before his real reign or terror began around AD 64-65. In the end he was declared a public enemy by the Senate and fled, taking his own life in a shameful manner in AD 68.

This coin is a bronze Sestertius struck at the Lugdunum mint in AD 65. It is a whopping 36mm in diameter with a weight of 26g. Because of its size I can't help wondering it it might have been issued as a presentation piece of some kind? The reverse shows the emperor on horseback with a soldier behind him. The legend "DECVRSIO" on the reverse is a reference to a mounted military advance, but according to Seth Stevenson in his 1889 "Dictionary of Roman Coins" may have been issued to mark Nero's establishment of cavalry drills amongst the Pretorians.