Maybe a dumb question but does casting the spell to upgrade mineral ores in public give a bounty? I mean you dont have to use it in public but if you do, I havent tried as I dont keep much gold on me. But say I did use the spell to make gold from silver could i pay the bounty with the gold? Probably not since its not septims but it is worth septims, so I guess thats the real question I have. BUT if my sneak were high enough would that work still?
The only things that get you a bounty are criminal offences.
I like to stir up Thalmor by casting familiars between them, and stuff like that. Unless it's an 'offensive' spell, which harms them or causes harm, it won't attract a bounty. If you want to try it, go find some chickens, but don't take a follower, and cast on the chickens...
If you really want to have a laugh, and have a spare few septims, wait until Thalmor walk past chickens in some of the villages, then cast frenzy onto the chooks....sure, it's dead chickens, but worth a good laugh, and with any luck one of the Thalmor will hit or spell a guard and then it's on for young and old.
The other way to start a fight with them, foolproof with no bounty attached, is to admit you worship Talos, or simply don't answer if they put the question to you...if you want a fight, you will have one, otherwise just leg it towards some guards, they'll jump in on your side.