Magic Tricks

To be clear - the vanish uses a gimmick that will not be able to be used for anything else. The appearance uses any ring and does not damage it at all (unless you drop it, in which case that's your own fault...). A wedding band would be perfect for the appearance, a large signet ring would not work so well because it would be harder to conceal. While not set up for a borrowed ring, you could make it work by borrowing a ring, vanishing it, then going into the appearing ring routine.

You have to use a ring that fits your finger. The production uses a move, not a gimmick. As jb implied, a ring that fits may be too wide for your fingers to conceal; and increases angle issues. The vanish uses a gimmick plus a move. Making the gimmick destroys the ring.

Only one effect requires a gimmick. You may be limited on the other one depending on the size of your ring (i.e. some people may find wider rings a little harder to work with).

Does it harm the ring in any way ie. Could I use my wedding band?

Great question! You have to use a prepared gimmick, which only works with the ring you prepare it with.