I think she should....at least it will let her/us know if it is crystal or glass. AND, there are two ways to find out. #1 Your suggestion above, which is an excellent idea. #2 My way..that always got me/my siblings/father and I in trouble at holidays when mom would pull out the fine crystal....and we would attempt to play tunes by simply wetting the rims of the crystal and run our fingers around it until the resonance was music to our ears. (To this day mom still gets irritated when I let my children/guests play my crystal!)
So, for the uninformed, I take this time to pass this fun event on for you to share with your families and friends....here's a video on how to! (Ha) science.howstuffwor ks.com/mpeg/wine.mpg
And for those that have to know why this happens, the best explanation I could find on the net is at answers.google.com/answers/threadview/id/156934.html
Amy, let us know!