|Smoke detector element.|
I'm told it's illegal to disassemble a smoke detector and remove the tiny radioactive dot that is contained in every ionization detector. But I did anyway, using an old one in May 2002. Considering that probably many thousands of these are disposed of (also technically illegally) in the garbage every year, I'm hardly the only one to mishandle the dots. My americium dot is now contained in a glued-shut box with a glass top that is harder to disassemble than the smoke detector was, and then inside a lead cup with a lid, just so our personnel manager doesn't freak out. (It was my first radioactive sample, but has since been vastly surpassed in radioactivity by the Fiestaware bowl.)
This article by Ken Silverstein (first published as "The Radioactive Boy Scout" in Harper's Magazine, November 1998) describes the amazing case of a teenage boy who did incredible (and incredibly dangerous) things with smoke detector americium. (The story is now available as a book by the same author.)
The sound is from the Geiger counter: I think most of the radioactivity is shielded by the glass cover glued in place over this sample, so it's not really representative (an unshielded one registers about 2000 counts per minute).
I chose this sample to represent its element in my Photographic Periodic Table Poster. The sample photograph includes text exactly as it appears in the poster, which you are encouraged to buy a copy of.
Source: Hardware Store
Contributor: Theodore Gray
Acquired: 15 May, 2002
Text Updated: 11 August, 2007
Price: $10/smoke detector