There are no coincidences in a game setting. If you lose a powerful item, you can bet your boots that you'll see it again, somewhere. You just better hope the somewhere is not in the hands of your enemies.
If Middle-earth was a game setting, tossing the One Ring into a volcano would have been the worst possible thing to do with it.
Transcript
GM: It's late here, it must be really late there.
Han: No, actually it's almost a whole day earlier.
{beat}
Leia: I think it's time for sleep anyway.
C-3PO: Good session!
R2-D2: Apart from the one we left behind. Again.
Chewbacca: If anyone can find it, it's us.
Han: Or you.
C-3PO: Or someone else.
Luke: These things always turn up again.
Leia: So basically we're saying someone in the Galaxy will get their hands on the Orb.
R2-D2: That makes me feel a lot better.