Some hit antique stalls with their CDV-700s cranked, hoping to spook dealers into a discount. Others surreptitiously palm an RM-60 while listening on earphones for telltale clicks from cheap old candy dishes and sickly pale-green milk pitchers. These mysterious men are a most obscure group of antique collectors, and they seek an invisible prize scorned by all others: radiation.
"[Look] for a particularly interesting item called a 'Radio-Sanitizer,' " advises one poster on CDV 700 Club, a Yahoo group of Geiger-geeks named after a classic counter. The item's a corrugated-metal water trough, he says, and, "They'll twist the meter right out of the instrument." Others talk Geiger models and swap war stories—literally. "The hottest radium-dialed object I ever found was a WW2 Japanese aircraft turn-and-bank indicator," writes a member. "It was STILL glowing noticeably under bright light. My Monitor 4 was reading 30mR/hr at the surface of the glass."
That's the hourly equivalent of about three chest X-rays. And thanks to a 19th- and early-20th-century love affair with radioactive luminescence and colorants by manufacturers and consumers alike—a houseware, medical, and technological boom that produced millions of toasty isotopic items—there's plenty more radioactive whup-ass where that came from.
"Collecting this is a bad idea," sighs Paul Frame, the Oak Ridge Associated Universities curator of what may be the country's definitive online radiation collection. From his tone, it's pretty clear that he gets called often by collectors. "It's hard to give useful advice other than 'Just stay away from it.' "
But even as we spoke, hundreds of buyers and sellers haggled over charming antiques that radiate more than just the glow of ownership. It's all online now, with no clunky CDV-700 units required. Where? EBay, of course.
This week was a fairly typical one in radioactive auctions, in fact, beginning with hundreds of pieces of spookily green glass, like this uranium absinthe cup. Produced in huge quantities, glass containing uranium compounds—now sold as uranium glass, canary glass, or Vaseline glass—tends to be the most faintly radioactive of collectibles, albeit with a great party trick: Canny eBayers reassure buyers of authenticity by picturing the stuff fluorescing alien-green under UV light.
Other hotly contested auctions include that much-loved 1950s kiddies' delight, an Atomic Energy lab (no, they were not falsely advertised); a 2-inch pod of "very radioactive" cuprosklodowskite that fetched $225 after 12 bids; and two pricey auctions for circa-1920 Revigator radium water coolers. You can find most isotopes without much effort on eBay. Bidding on old Coleman camping lamp mantles? Thorium. Vintage Doramad Radioaktive Zahncreme ("radioactive toothpaste"), used by Germans to keep teeth gamma-ray bright? Radium, with even a squished-out tube fetching a high bid of $122.50. Old spark plugs? Polonium. Still other auctions are evidence of a jazz-age infatuation with radium as the byword of the future, like this Lee's Radium Shaving Razor—a steal, won with a single 99-cent bid.
"Many items simply weren't radioactive," Frame muses. "Radium was used then the way gold or silver is today—for instance, a gold card wouldn't have real gold in it." Even so, you might want to think twice before bidding on an old tin of Tho-Radia face powder—because the stuff really did contain both thorium and radium, an inhalation hazard that your lungs will not thank you for.
If you look, millions of bona fide radioactive antiques are out there—Oak Ridge even publishes A Collector's Guide to Radioactive Dinnerware (pdf file). The red-orange hue in old plates by Fiesta Dinnerware and its imitators was achieved with uranium oxide, though the ore supply was interrupted by the U.S. government in 1942 for use in, ahem, other projects. Topping out with a surface reading of about 3 or 4 mR/hr, uranium glazes don't pack a killer punch. Granted, one 1996 study did produce uranium leachate by microwaving acidic foods—but al-Qaida won't be planning its next attack with vintage butter dishes. "To really do some harm, you'd probably have to sit on it for a month or two," notes science writer Theodore Gray in his superb online gallery. The greater danger is lead: Enough leached in during the microwave experiment to exceed an adult's weekly suggested exposure.
So, how much radiation are you getting from this stuff? In many cases, maybe not much more than naturally occurs in your home. The radiation collector's bible—William Kolb's self-published and utterly engrossing Living With Radiation—is quick to point out that lots of common objects are faintly radioactive. Bananas, brazil nuts, cat litter, granite countertops, sensitive toothpaste ... even dryer lint boasts 20 times the background rate of radiation. (Don't blame your appliance: Naturally occurring radioactive isotopes adhere to dust.) Exposure also varies greatly by distance—and there's probably more danger from a uranium oxide pendant on your skin than from that plate on your shelf.
Even so, Kolb and Frame both avoid one type of radioactive antique—and startlingly, it's the one the rest of us are most likely to own. "I shy away from anything that contains radium," Kolb tells me. "In most cases, radium is not fixed in a way that eliminates the risk of contamination or ingestion." And where would Joe Public find that radium today? Simple: in old watches. "There were probably 100 million watches made in the U.S. alone during the era of radium dials," Oak Ridge's Paul Frame says. "There's so many of these things."
Many stopped luminescing years ago, so their radioactivity is not obvious to the casual observer. But it's still very much present, and will be for millennia. The relatively short half-life of the RA-226 isotope (1,602 years) means that it has lots of decay going on—radium puts the active in radioactive—and inhaled or digested radium dust presents a particular danger because its bodily absorption mimics calcium. It can go right to your bone and marrow, as unfortunate dial-factory "Radium Girls" discovered in the 1920s.
One YouTube clip shows the dramatic squawk an old Timex watch face can still coax from a Geiger counter. Take off the glass bezel and you're asking for trouble—and not just from the radiation. "The Nuclear Regulatory Commission is about to clamp down," Frame warns me.
Amazingly, the NRC lacked regulatory control over consumer radioactives in the past; that was left to the desultory enforcement of states. But buried in regulatory language and unnoticed by any news media, last month the NRC quietly announced a change in policy: It can now require a general NRC license from any owner of an object containing more than 37 kBq of Radium-226. That's about twice the typical content of an old mantle clock, four times that of a pocket watch, and about six times that of a typical wristwatch. Collectors with particularly hot timepieces—or with many typical old ones—may now fall under the NRC's regulations, as may eBay auctions of multiple radium parts like this one. Any CDVer with an old crate of 100 luminous gauges (or radium chain pulls, or anything else that glows) will also need a general license—and so will Revigator owners. That means you can't export, disassemble, or dispose of the stuff without NRC approval.
The news has not even reached the happy hunting grounds of the CDV 700 Club yet. Instead, a recent post reminisced about how, "The hottest rock that is not 'ore' that I've Urban Prospected was in an antique store, appeared to [have] been a green marble smoking stand. It was hotter than a firecracker compared to most."
It's an appropriate find for radiation hunters: Because now, it seems, you'd better smoke 'em if you've got 'em.