Under this patina do we have Vespasian, or do we have Titus, or do we have someone else? What do you think on that score? (I think that we have VESPASIAN - but not Vespasianvs) on the obverse, and I am pretty sure that we have 'CONCORDIA AVGVST' on the reverse.)
I'd like to think that it is Vespasian, but after looking in CNG, Acsearch, and Wildwinds, I don't seem to be able to find a 'left' facing bust with Concordia (or even Annona or Tutela) and that (corresponding) legend. (Edit)
Vespasian does have left facing busts with Concordia, however they are fairly rare. Without knowing the obverse legend it will be difficult to accurately attribute.
Looks like a 'cleaning' job coming up. Any ideas on how to remove the brown (stuff)? (DM water and a toothbrush doesn't do it.)