I was pleasantly surprised to find a Trebonianus Gallus IVNO MARTIALIS silver antoninianus in a lot of uncleaned coins I purchased from a seller in Serbia.
I bid on the lot because there was a VIRTVS AVGVSTORVM AE-3 of either Constantius II or Vetranio in it. There were no photos of both sides in the auction but it's the second from the right on the bottom row). It turned out to be Constantius II and it has issues with broken patina areas.
However, there were several other nice coins in the lot including the Gallus. It was heavily encrusted and I thought it was most likely a fouree. It is the coin in the upper left of the seller's photo.

However, after some cleaning I started to wonder if it might be the real deal so I put it in lemon juice and it cleaned up nicely.
It has some copper/red deposits of "horn silver" (I think that's what it's called) on it, but is a decent coin.


The reverse is interesting and one I hadn't seen before. The IVNO MARTIALIS reverse was only used by Trebonianus Gallus and his son Volusian. I came across this link that talks about it:
https://www.cointalk.com/threads/ju...alis.329837/