I have recently come across these two Sasanian Dinars sold recently in CNG auction 124- Lot 410-411. (Photos attached) Just pay attention to details on each coin obverse and reverse, they look exactly the same on each side and this is one of the bad signs for collectors. Having EXACTLY the same obverse and reverse is on of the sign of a forgery, as it is super rare to come across two or more than two coins with exactly the same obverse and reverse dies. The reason is that reverse die is the one that get hammered and wears off quicker than obverse ones, and apparently it took 4-5 reverse dies for obverse die to get completely worn off or broken and out of use. and specifically of this type of Dinar which is not a very common one, with a previously reported forgeries in the market, is a very bad sign, and putting them up as two lot one after another by one of the well- know auction houses in the world just can’t convince me of a mistake! (If you know what I mean) Finally, it’s just SAD that where numismatic market is going. Don’t get trapped by big names and always do your own research.
I believe many of these being sold came from a somewhat recent hoard so it wouldn't be surprising for them to share dies. They used to be rare and very expensive, but aren't any longer. Of course I could be wrong, but I bet these coins are fine.