I think
RIC is rather confused about this issue, and also confuses it with the earlier (lab tested as ~20% silver) billion issue from c.312-313 (
RIC VI Trier 825). It can certainly be hard to tell apart billion (
RIC VI 825) and patinated billion from
silvered or patinated AE (
RIC VII 210-212).
According to
RIC we have:
RIC VI 825 P S straight wing } Billion
RIC VII 211 P bent wing } AE (originally silvered)
RIC VII 212 S straight wing }
I'm omitting
RIC VII 210 since it has a different
bust type and therefore can't be confused (the
RIC description is correct - bent wing, off. S).
In reality, I think what exists is:
RIC VI 825 P straight wing } Billion
RIC VI 825v P bent wing }
RIC VII 211 S bent wing } AE (originally silvered)
RIC VII 212 S straight wing } <-- but I've never seen one
You'll notice that the c. 312-313 billion issue appears to only exist for "
officina" P, since at that time the
mint is believed to have only been operating a single
officina, and in fact the PTR
exergue at that time really means
Pecunia of TRier, not Primary
officina of TRier. Additionally I believe (I've yet to see a convicing counter-example) that the AE
types were only issued from
officina "S" to avoid confusion.
The
RIC VI 825 listing for
officina "S" appears to be an error, and is really
RIC VII 211. Additionally the
RIC VI 825 plate
coin shows a bent wing (which I'm referring to as 825v), vs the "spread wings" description which I'm taking to mean straight
per the
RIC VII usage of those terms.
The
RIC VII 211 listing for
officina "P" appears to be an error, and is really a
RIC VI 825 variation (bent wing vs straight), but this
type does exist for
officina "S".
Eric's coin is nominally
RIC VII Trier 211 (bent wing), but I'm not 100% convinced that the coin is official, or that if it is official it may not be a patinated
RIC VI 825v. The issues with the coin being official are the VG vs
AVG, the unexpected
officina "P" for the AE issue (first I've seen - and I have quite a large
collection of images of this
type), and it seems that the
eagle may be standing on a straight vs wavy line.
To illustrate straight vs bent wing, here's the difference for the billion issue. The first coin is my own and is
RIC VI 825, the second is what I'm calling
RIC VI 825v, also billion.
Ben