I recently acquired this Vespasian sesterius for two reasons - it was affordable and it has an interesting flaw. Vespasian Æ Sestertius, 25.22g Rome mint, 71 AD Obv: IMP CAES VESPASIAN AVG P M TR P P P COS III; Head of Vespasian, laureate, r. Rev: S C in field; Mars adv. r., with trophy and spear RIC 199 (C2). BMC 777. BNC 539. Acquired from Incitatus Coins, April 2020. Struck during the great bronze issue of 71, this reverse features the standard Mars as a 'heroic nude', similar to the same type struck on the denarius. Mars here can best be interpreted as a triumphal type, likely based on a cult image. I assume the planchet flaw on the reverse was a happenstance of its production, but I really don't know. Any enlightenment would be much appreciated! Feel free to share your flaws!
I would guess the mint realized the flan was too large and loped off a piece. What would theis have weighed if it were round and even?
Could the damage have been done post production? I take it that it corresponds to the understruck/flattened areas at about 5 o'clock on the obv. Could the obverse have been damaged by something (no idea... but some form of large impact) hitting that area of the coin? Or as @dougsmit suggests that the flan was trimmed pre-strike and this caused that area to not take the obverse image from the die in that area.... Nice coin regardless.
I would guess the flaw was there when the coin was struck, for the same reason maridvnvm mentioned--the understruck area on the obverse. Unlike gold or silver coins, nobody really cared about the exact amount of bronze as long as it was large enough to distinguish from a dupondius. If someone was stamping coins and came across a damaged flan like this, they most likely would have gone ahead and stamped it anyway. They certainly wouldn't have thrown it out. Whether it was an unfilled mold or a weak spot in the flan that broke off before it was stamped, I have no idea. Were individual flans made from molds at this time, or from trees, or were they just lopped off a longer bar?
I was think along the same lines ... a pre-strike flaw that wasn't considered a big deal during production. Although, the understruck area of the obverse does not correspond with the flaw on the reverse. My understanding of flan preparation at Rome during this time period is that the flans were chopped off of metal bars/rods.
The coin is in the proper weight range, so it looks as if the flan was improperly cast, creating a flan flaw. The obverse seems to be weakly struck, and I assume that this are corresponds to the tapered edge on the reverse. An uneven surface will affect the pressure created during the striking process, causing weakness towards the edge on the obverse.
Interesting. Possibly the flan shifted during striking in a manner that created weakness of strike on the opposite side of the flan flaw? Could there be die wear involved? During the 71 CE issue of Vespasian bronzes, it seems that quality control was not a high priority. That year also saw the issuing of the Judaea Capta series, which continued for 25 years during the reigns of Vespasian and Titus. These coins undoubtedly were used to project Rome's triumph and dominance throughout all corners of the empire and beyond.
