As an alumni of St. Francis Xavier University in Antigonish, Nova
Scotia, we've always heard (and believed) that our X-Ring (see
http://www.stfx.ca/icons/stfx/xring-color-96.jpg) was the "third most
famous ring in the word", after the Pope's ring and the Superbowl
ring. Supposedly, this was substantiated by a question on "Jeopardy!"
at one point, but nobody can actually verify this.

My questions, then, are as follows:

1) Is the StFX X-Ring REALLY the third most-famous (or
most-recognized) ring in the world?

2) Was such a question regarding the X-Ring ever actually asked on
"Jeopardy!", and, if so, when?

I doubt that such a question would have appeared on "Jeopardy!" 

The questions on "Jeopardy!" are typically questions which have only
one correct, verifiable answer. There is no ironclad standard for
"most famous." Different surveys may find different results. If a
question like this were to be used on a quiz show, it would almost
certainly be subjected to challenges by losing contestants, who could
cite their own authorities on famousness.

I doubt it as well, but I'm just trying to formally prove or disprove an old legend.