The top picture shows the three sisters of Caligula; Agrippina, Drulsilla & Julia; in the form of the Three Graces. I can not tell anything from the next two pictures. If you can read letters, you should post them with the pics.
I cant make much out of the photos. If there are three figures on the reverse, there were plenty of provincial issues with the Three Graces, all down to the Third Century. Portrait kind of looks like Trajan, but better photos would be needed to properly attribute it. Oh, BTW, its not a Caligula!
