RSC 45, the OP is RSC 46 ( **or rather is suposed to be**) The S C in the fields and the lituus is the main difference.
Just to complicates our lives a bit more, that coin that Bing posted is tooled. I wouldn't have guessed until I saw a before picture below, Before, 3.74g and 3.70g after.
The reverse on the lower coin is more than just tooled; letters have been added to the legend above the bull. In the top coin, only the letters NIUS exist; in the altered version, the full VOCONIUS exists. This is reprehensible. This coin is essentially worthless to a serious collector.
The tooled coin was listed and subsequently withdrawn, prior to the auction, by Roma Numismatics in Oct. 2011 at their Auction 2. So apparently they recognized it had been significantly altered. With unintentional irony, they had described the coin as follows: "This portrait is of masterly style, having clearly been engraved by an individual of substantial talent." Just not by an ancient engraver... I'm unable to locate the auction at which it did sell -- can you provide this information?
What auction house sold that? I want to report this to them. If they are reputable they need to refund that buyer, because he got conned big time.
I found it. The altered coin was sold by: Helios Numismatik GmbH Auction 5, Lot 196 25 June 2010 Hammer price 10,000 EUR (approx. $12,380 U.S. NOT including buyer's fee). The original (non-altered) coin was sold by: Auktionhaus H.D. Rauch GmbH Summer Auction 2009, Lot 566, 17 Sep. 2009 Hammer price 1,600 EUR (approx. $2,360 U.S. NOT including buyers' fee). Edit: Note that the Roma auction, at which this coin was offered and withdrawn prior to the actual auction, was about a year after this coin was purchased from Helios. I wonder if the purchaser was told by Roma that the coin was altered and tried to get a refund from Helios?
I've never seen such a massive alteration so well executed on a coin. I can't figure out how it was done, almost as if material was added to the coin.
Material was definitely added to the coin -- there is no way to add the letters in VOCONIUS on the reverse by engraving.
I believe there is a way which is worse than tooling. Could the original coin been used to produce a copy die which could be 'touched up' and used to strike a 'replacement'?
I would say yes to your theory, and I think that does happen, but on this coin there is chipping at 4h which I doubt could be transferred easily to a copy or would be transferred if you were modifying the original. Yeah, this is a very dangerous coin.