Answer to Question #5847 Submitted to "Ask the Experts"

I am interested in obtaining some radioactive mineral specimens. On several Web sites, specimens of pitchblende (uraninite), cleveite, autunite, saleeite, davidite, torbernite, and others are offered for sale to collectors. Given that some of these specimens may weigh as much as 1,000 gm and, in the case of pitchblende, may contain in excess of 80 percent by weight of the mineral (that is, 80 percent pure uraninite, 20 percent gangue), what are the hazards in owning, collecting, or otherwise having these specimens in a mineral collection?

Lots of folks collect geological specimens containing uranium (I even have couple of uranium ore-bearing rocks on display in my hallway at home) and so long as you do not have large numbers of samples, or samples quite rich in uranium, they should pose no problem but need to be handled with care. Natural uranium is only weakly radioactive and its chemical toxicity is actually of greater concern. Thus, the mineral samples should not be handled frequently, or for very long periods, and the hands should be washed after handling. Obviously one should not carry the specimens in one's pocket or keep them around food. Children should not be allowed to play with them. They should generally be kept away from folks as much as practicable, and it would be well to shield the specimens containing more than a few tens of grams of uranium when they are stored or displayed. Shielding against the beta radiation can be accomplished by a sheet of Lucite^_TM or other clear plastic at least 1/4-inch thick. This will allow the specimen to be viewed but will greatly reduce the radiation field associated with it.
 
Ron Kathren, CHP