You recall that story from a coupld of weeks ago about uranium yellowcake being found in Rotterdam ?
I was doing some work for the day job at LHFC ( motto : Scandium, Crunchy! ) when I cam across this page about hazards in ceramics.
The amount of yellowcake found, and which may or may not have come from Iraq, was 5 1/2 lbs.

Beware of old supplies lingering around and being passed from potter to potter or from teacher to teacher. I once discovered a brown paper bag with several pounds of earthy yellowish powder in a school supply cabinet in a high school classroom. When tested with a geiger counter it emitted significant radioactivity. It was uranium oxide apparently still there from a time prior to World War II when it was commonly sold as a glaze colorant.

To put the find of WMD into perspective : about the same as can be found rootling around a US high school.