I just had a fight, where the enemy exploded a bounty gem. Instead of the little gold coin, it dissolved just in a puff. Before the enemy was at 0 gold, afterwards too.
I was a bit hurried (late in a pet hunt), so I could not check this too much in detail, and a simple screenshot of a battle stat screen would not have helped either.
Would someone else maybe run a few practice fights against a couple of Leprechauns or something to countercheck, if I noticed this correctly?