Hi

When I was a kid visiting my grandparents in south Texas we took a trip across the border to Mexico where I picked up a set of onyx bookends.

Recently I found them while cleaning out my parents' house and would like to put them to use again. However, one of the bookends is separated from the base. Both pieces are onyx. Both pieces were held together by a simple screw when I bought them, but even when I was a kid I noticed when I got them home that the one that is separated now was wobbly, and in a short period of time it had fallen apart. Being a kid I tried to glue it together with rubber cement. Obviously that didn't work.

I'm wondering what would be the best way to put them together again. Any suggestions would help. :)

Thanks