I listened to the books (as opposed to reading them) and waited until I listened to The Hobbit before posting this question. Please forgive me if I remembered it incorrectly.
After the destruction of the One Ring, and after Galadriel travels with Frodo and company, she waves her hand as she walks away. Frodo sees a spark from her ring. What was the spark and why was Frodo the only one who saw it?
With the One Ring destroyed, the rings may have lost their power. Meaning, the rings should not be invisible and the spark was simply the sun glinting against the metal. But then everyone should have seen it.
If the rings still had some power and were still not visible, Sam, as a ring bearer, should have seen the ring as well.
I would guess in answer to my own question that the others did indeed see it, but it was only Frodo who found it significant. Or am I missing something entirely?