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Comment by dynm

1 month ago

Fun fact: Americans are seemingly allowed to own up to 1.5 kg of yellowcake. (That's pure uranium, refined from uranium ore, but not enriched to extract the 0.7% U-235 from the 99.3% U-238.)

Citation: https://www.nrc.gov/reading-rm/doc-collections/cfr/part040/p...

> That's pure uranium,

Not exactly.

Yellowcake is about 80% uranium oxide:

"Triuranium octoxide (U3O8), the most stable uranium oxide; yellowcake typically contains 70 to 90 percent triuranium octoxide)"

https://en.wikipedia.org/wiki/Uranium_oxide

  • The atomic weight of Uranium is 238; the atomic weight of Oxygen is 16. By weight, Triuranium octoxide is ~84% Uranium. Even if you're only counting the uranium in the Triuranium octoxide, that's still 60+% of the total mass coming from Uranium Atoms. I'd take that purity any day.

According to that link that's for dispersible form (gas, powder) – it's up to 7kg in solid form ¯\_(ツ)_/¯