The "Gilbert U-238 Atomic Energy Lab Kit," the Most Dangerous Toy in the World.

Marshall Field & Co. State Street Store sold the U-238 in Christmas 1950, according to  a former Toy Dept. employee.

"Gilbert U-238 Atomic Energy Lab Kit."

The most dangerous toy in the world.

The set originally sold for $49.50 ($630 today) and contained the following:

1. Battery-powered Geiger–Müller counter.
2. Electroscope.
3. Spinthariscope.
4. Wilson Cloud Chamber.
5. Four glass jars containing uranium-bearing ore samples (autunite, torbernite, uraninite, and carnotite from the "Colorado Plateau region") served as low-level radiation sources of Alpha particles (Pb-210 and Po-210).
6. Beta particles (Ru-106).
7. Gamma rays (possibly Zn-65).
8. "Nuclear spheres" are used to make a model of an alpha particle.
9. Gilbert Atomic Energy Manual — a 60-page instruction book.
10. Learn How Dagwood Split the Atom — comic book introduction to radioactivity.
11. Prospecting for Uranium — a book.
12. Three C batteries.
13. 1951 Gilbert Toys catalog.

  Chicago Tribune, Wednesday, May 17, 1950

Atomic Kits for Kiddies, Latest in Toys.

The Gilbert U‑238 Atomic Energy Lab Kit: Because What's Childhood Without a Little Uranium?

Back in 1950, when American kids were busy launching model rockets from the backyard and seeing how many firecrackers it took to blow up a tin can, A.C. Gilbert looked at the nation's youth and thought: "You know what these boys need? Radioactive materials.” And thus, the Gilbert U‑238 Atomic Energy Lab Kit was born—an educational toy so audacious it makes chemistry sets look like coloring books. 

Packaged in a sleek metal case, this beauty came stocked with actual uranium-bearing ores, a Geiger counter, a cloud chamber, a spinthariscope, and even a comic book where Dagwood Bumstead learns how to split the atom. Because nothing says "wholesome American childhood" like watching alpha particles zip by at 12,000 miles per second while Dagwood explains nuclear fission. 

Gilbert—athlete, magician, toy-maker, and all-around “let’s see what happens” kind of guy—believed toys should build a solid American character. And what builds character faster than handing a kid a jar of uranium ore and telling him not to break the seal because it “tends to flake and crumble”? Boys will be boys, after all. 

Sure, the kit cost $49.50 (about $660 today), but you weren't just buying a toy—you were investing in your son's future career as a nuclear physicist… or at least giving him bragging rights over every kid on the block who only had an Erector Set. 

Gilbert insisted the materials were “completely safe,” certified by Oak Ridge Laboratories. And if a little radioactive dust happened to raise the background count in your basement laboratory? Well, that’s just part of the fun. Boys will be boys, and sometimes boys irradiate the basement. 

The government even encouraged the kit’s development, hoping it would teach kids the constructive side of atomic energy. And it did—if by constructive you mean constructing a generation of kids who could identify beta, gamma, and alpha sources before they could drive. 

The kit didn't last long—1950 to 1951—mostly because parents weren't quite ready to add "radioactive decay” to the list of acceptable household hobbies. But collectors today will pay more than 100 times the original price for a complete set. Boys grow up, but the allure of glowing rocks never fades. 

In the End…

The Gilbert U‑238 Atomic Energy Lab Kit remains one of the most spectacular, ridiculous, and charmingly reckless toys ever sold. It's a relic of an era when America believed in science, progress, and giving children just enough radioactive material to keep things interesting.

And honestly?

It's hard not to admire the sheer audacity.

Because after all—boys will be boys!!

========================================================================

 

The "Gilbert U-238 Atomic Energy Lab Kit," the world's most dangerous toy.

The Gilbert U‑238 Atomic Energy Lab Kit: Because What's Childhood Without a Little Uranium?

 

Back in 1950, when American kids were busy launching model rockets from the backyard and seeing how many firecrackers it took to blow up a tin can, A.C. Gilbert looked at the nation's youth and thought: "You know what these boys need? Radioactive materials.” And thus, the Gilbert U‑238 Atomic Energy Lab Kit was born—an educational toy so audacious it makes chemistry sets look like coloring books. 

Packaged in a sleek metal case, this beauty came stocked with actual uranium-bearing ores, a Geiger counter, a cloud chamber, a spinthariscope, and even a comic book where Dagwood Bumstead learns how to split the atom. Because nothing says "wholesome American childhood" like watching alpha particles zip by at 12,000 miles per second while Dagwood explains nuclear fission. 

Gilbert—athlete, magician, toy-maker, and all-around “let's see what happens” kind of guy—believed toys should build a solid American character. And what builds character faster than handing a kid a jar of uranium ore and telling him not to break the seal because it “tends to flake and crumble”? Boys will be boys, after all. 

Sure, the kit cost $49.50 (about $660 today), but you weren't just buying a toy—you were investing in your son's future career as a nuclear physicist… or at least giving him bragging rights over every kid on the block who only had an Erector Set. 

Gilbert insisted the materials were “completely safe," certified by Oak Ridge Laboratories. And if a little radioactive dust happened to raise the background count in your basement laboratory? Well, that’s just part of the fun. Boys will be boys, and sometimes boys irradiate the basement. 

The government even encouraged the kit’s development, hoping it would teach kids the constructive side of atomic energy. And it did—if by constructive you mean constructing a generation of kids who could identify beta, gamma, and alpha sources before they could drive. 

The kit didn’t last long—1950 to 1951—mostly because parents weren’t quite ready to add “radioactive decay” to the list of acceptable household hobbies. But collectors today will pay more than 100 times the original price for a complete set. Boys grow up, but the allure of glowing rocks never fades. 

In the End…

The Gilbert U‑238 Atomic Energy Lab Kit remains one of the most spectacular, ridiculous, and charmingly reckless toys ever sold. It’s a relic of an era when America believed in science, progress, and giving children just enough radioactive material to keep things interesting.

And honestly?

It’s hard not to admire the sheer audacity.

Because after all—boys will be boys!!

 

MORE FOR TEENAGERS

"This outfit is more for teenagers than for kiddies," the spokesman said. "We expect it to do a great deal to promote the understanding of atomic energy." The same company has manufactured chemistry sets.

A boy, owner of an atomic energy laboratory, will be able to hide his isotope under a rug and locate it by the Geiger counter, it was said. He can put the isotope in a dark room and, with the aid of a spinthariscope, watch atomic disintegration manifest as sparks.

The spokesman said the AEC and postal authorities have approved the manufacturing and distribution of the kits. The company is the A.G. Gilbert Manufacturing Company.

HALF-LIFE ISOTOPES

The AEC said in Washington DC that the isotopes sold to the toy company are known as "Zinc 65" with a "half-life" of 250 days.

The meaning of the term half-life was not explained. The AEC said it understood the company proposes to make toys in which children can watch atomic disintegration.

Compiled by Dr. Neil Gale, Ph.D.