Forming a ball with Sterling wire

I am new at metalsmithing and have something I’ve always wanted to do
but don’t know how. Here is the question:

I want to melt sterling wire to form a ball at the end. I need to do
this very close to semiprecious stones. What do I use? I have
included a photo to show a design which I make loops at the ends of
the stones. I would like to have balls instead like headpins.

Thanks for any tips.