Got a few bit of radioactive stuff I've collected over the years.
A nice uranium glass candy bowl:
Not particularly active, but still measurable over my room's background of 25 CPM.
Some uranium glass beads:
More active than the candy bowl, which given its much lower mass must mean its got a higher concentration of uranium, and/or it was made much more recently (the candy bowl is from the 1920's)
Core of an old smoke detector (contains americium and its decay components):
Not much happening with that either. Americium primarily emits alpha radiation, which my counter can't detect (and alpha wouldn't make it through the metal casing anyways) but its decay components emit radiation that I can measure. I imagine the reading would be higher if I could get the americium pellet out of that casing.
And last but most certainly not least, an nice large uranium ore-laden rock I purchased off ebay:
Looks inconspicuous enough, but the geiger counter tells a different story:
Quite an active specimen! I would love to measure it with an alpha sensitive counter. Its mostly giving off low energy beta radiation so its not particularly hazardous. The main worry is little bits of it breaking off and inhaling or ingesting uranium ore dust and letting that bake my innards.
I would love to get a nice intact radioactive fiestaware plate, but they are a bit expensive on ebay and I've never been able to justify spending a lot on a plate just to make my geiger counter tick.