I started wondering this after the extremely gratuitous slo-mo pearls in Batman vs Superman, but forgot to google it after leaving the theater. Then I mentioned it in chat tonight when I saw the same thing happen in Batman (1989), and Wad found several more examples, so it's probably worth asking:
Does Martha Wayne always wear a pearl necklace when she gets killed, and does that necklace always fall apart so that we see individual pearls falling to the ground? Obviously, any version of Batman's parents is acceptable, no matter how obscure.