re: Anyone here use metal detectors as a hobby?

When I was working at a sports card memorabilia shop one year, I believe it was Donruss that put out a special set a cards you could collect inside the individual packs. The cards were made with some kind of metallic gold leaf flake type paint or something like that.

We used an old school stand up type sweeper metal detector to scan each pack to find those cards. Worked pretty well.

That's all the experience I have. Hope that helps.