I really enjoyed this post - I knew very little about this issue and now I know more. And I love HBO's Rome...although in the scene where Pullo gets swindled at gambling (and gets his head bashed in), didn't the coins they use look too large? They looked like tetradrachms...a minor complaint about a wonderful show. My only Glabrio is pretty sorry - very worn, overly cleaned, and banker's marks.
Lol... I remember hitting the pause button a few times to scrutinize the coin props used in the scene. They definitely did not look right.
Yeah, I think in movies set in ancient times, they bump up the size of the coins because otherwise it looks as if everybody is getting excited about (or getting in fights over) a handful of dimes. I did like it in Rome when Lucius Vorenus was paying the surgeon for fixing Pullo's skull and the doc, without missing a beat, hands back one of the coins and says (as I recall) "This one's brass." A near-reference to a fourree, perhaps?