Just to be on the safe side, I brought my geiger counter home from work, where it was part of my cube curiosity collection (What? Your office wouldn't let you keep a geiger counter in your cube? Have I mentioned I have the awesomest job ever?) and scanned the batch of steampunk jewelry that I'm taking to SPX.
One of the hair barrettes will not be attending the show, it seems. It's probably okay -- it was giving off less radiation than even one of the smallest radium watch-hands -- but it was still making the needle jump more than I was comfortable with. I'm 99% sure it's the watch face, so I'll have to wait until I can find a suitable replacement for it.
Bummer; it was my favorite piece. Oh well.