What should I put in my locket?

Right, my locket is silver and has pearls and quartz stones over the 'lid' and on the back it says: "How do I love thee, let me count the ways." it is extremely old and VERY beautiful. Its shaped like an oval, but the ends are pointed and it measure 1 by 1.7 cm exactly. I don't have any of my baby hair to put in it, and there's no way it'd be able to hold a photo without it falling out. I think it'd be a bit gross to put in a tooth and I can't think what else I COULD FIT IN THERE... Please help, it's been empty for ages...