J.B.
If she likes and wears jewlery, then some nice jewlery sounds perfect. If she's not a jewlery person, is there something she's planning on doing with her free time? $500 could go a long way towards supporting her passions or hobbies (nice camera, bicycle, golf clubs, a kayak, iPad or other tablet, a laptop, video camera etc.). For my dad, his gift was mostly the party that we threw him - it was a catered event with 40 guests and that's really what he wanted instead of a physical gift, so that's another consideration.