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This paragraph later in the article is odd: > In March 2018, police in Ankara seized a whopping 1.4 kilograms (3.1 pounds) of a substance, believed to be Calif

This paragraph later in the article is odd: > In March 2018, police in Ankara seized a whopping 1.4 kilograms (3.1 pounds) of a substance, believed to be Californium, in a car following a tipoff. That time, however, the substance turned out to be organic with no nuclear or radioactive properties. That's a strange way of saying they seized "a whopping 1.4 kilograms" of nothing. Kind of makes you question the merits of this story/seizure. Least of all since them seizing the wrong thing a second time seems far more likely than someone driving around with $72M worth of a rare substance which can only be made in two places on earth (neither of which are Turkey).

atemerev 7y ago
Nuclear smuggling is relatively commonplace. I can recommend the book "Nuclear Forensic Analysis" by Ian D. Hutcheon, Kenton J. Moody, and Patrick M. Grant for those who are interested in the details. Minor quantities of genuine nuclear materials (tens of grams of plutonium) are seized at borders about once per year. Cases dealing with major (kilogram) quantities seem to be classified, but I have little doubt they exist.
- slang800 7y ago
  > I have little doubt they exist. One well known incident involved 91-272 kg of enriched Uranium going missing: https://en.wikipedia.org/wiki/The_Apollo_Affair https://en.wikipedia.org/wiki/The_Apollo_Affair
  - noobermin 7y ago
    Uranium (even enriched) seems like on a different level than Californium.
- solveit 7y ago
  I'm sure they exist, but there are no cases involving kilograms of Californium since there exist maybe ten grams of the stuff in the entire world.
  - mehrdadn 7y ago
    Ten grams in the entire world? I see photos of what is claimed to be solid californium here... is that fake: http://www.chemistrylearner.com/californium.html http://www.chemistrylearner.com/californium.html
    - petschge 7y ago
      The image labeled "Californium bullet" actually shows laboratory neutron sources that contain 5 mg of Californium. The rest of the "bullet" is actually a stainless steel casing. The metal shaving further down the page are most likely microscopic, but as no length scale is given it is hard to estimate the mass.
      - ars 7y ago
        That website also claims Californium is used to make jewelry. Personally I have my doubts about that
  - atemerev 7y ago
    Of course. Here I was talking about HEU/Pu.
foobarian 7y ago
> a whopping 1.4 kilograms (3.1 pounds) of a substance, believed to be Californium That's preposterous. Californium is not naturally occurring and costs tens of $M per gram to produce. Anyone who paid attention in high school should see big flashing alarms when reading a claim like that.
- ars 7y ago
  That much Californium in one place would probably go critical anyway. It might not explode, but it would glow and evaporate rather quickly.
  - petschge 7y ago
    Critical mass of Cf-249 is 6kg, of Cf-251 5.46kg and of Cf-252 is 2.73kg. So no it would not go critical. 1.4 kg of Cf-252 would however emit something like 4e15 neutrons per second and 1.2kW (I first thought it was 700kW) of decay heat. Glowing and evaporation would be rather likely.
    - LeifCarrotson 7y ago
      700 kW emitted by a grapefruit-sized object will be a white-hot, rapidly-expanding gas cloud. Maybe it's not a nuke, but I don't know that your decay heat math is correct...half a critical mass of uranium or plutonium is slightly above room temp, not something that violently disintegrates. Is Cf252 different?
      - petschge 7y ago
        You are right, the 700kW was wrong. The calculation I did was as follows (and I will point out the mistake I made): 1.4 kg is 1.4e9 micrograms and as per [1] "one microgram emits 170 million neutrons per minute" will emit 1.4e9 * 1.7e8 / 60 = 4e15 neutrons per second. Decays of Cf-252 have a high neutron multiplicity, about 3.7 per decay, so the neutron came from 1.1e15 decays per second. Most of those (> 95%) came from the decat Cf-252 -> Cm-248. The masses of those two isotopes is 252.081626 and 248.072349 atomic mass units respectively, as per [2] and [3]. An alpha nucleus of 4.001506179127 u is also produced. (If forgot about that one, vaastly overestimating the decay heat.) A mass loss of 7.77e-3 u is equivalent to the release of 7.77e-3 * 0.9314941 GeV / u = 7.2 MeV. Each MeV is 1.60e-13 J. So in total we get 1.1e15 decays per second * 7.2 MeV per decay * 1.60e-13 J / MeV = 1.2 J/s = 1.2 kW. If you forget that the alpha nucleus exists you over estimate the mass loss by a factor 500 and get a decay power of 700kW... [1] http://nuclearweaponarchive.org/Nwfaq/Nfaq6.html#nfaq6.2 http://nuclearweaponarchive.org/Nwfaq/Nfaq6.html#nfaq6.2 [2] https://en.wikipedia.org/wiki/Isotopes_of_californium https://en.wikipedia.org/wiki/Isotopes_of_californium [3] https://en.wikipedia.org/wiki/Isotopes_of_curium https://en.wikipedia.org/wiki/Isotopes_of_curium
gridlockd 7y ago
Quoting the source of that story: "According to Monday's NTV article, the suspects were reportedly in possession of a cache of Californium weighing 1.441 kilograms that they planned to sell for $72 million on the black market." So, back in 2018, suspects were trying to sell 1.4 kg of a substance claimed to be Californium for $72 million. Now, in 2019, suspects were trying to sell a mere 18.1 grams of a substance claimed to be Californium, again, for $72 million. I am trying to imagine a gang of schmucks still trying to sell baking soda as Californium but now they adjusted the price to be more realistic.

atemerev 7y ago

Nuclear smuggling is relatively commonplace. I can recommend the book "Nuclear Forensic Analysis" by Ian D. Hutcheon, Kenton J. Moody, and Patrick M. Grant for those who are interested in the details. Minor quantities of genuine nuclear materials (tens of grams of plutonium) are seized at borders about once per year. Cases dealing with major (kilogram) quantities seem to be classified, but I have little doubt they exist.

slang800 7y ago
> I have little doubt they exist. One well known incident involved 91-272 kg of enriched Uranium going missing: https://en.wikipedia.org/wiki/The_Apollo_Affair https://en.wikipedia.org/wiki/The_Apollo_Affair
- noobermin 7y ago
  Uranium (even enriched) seems like on a different level than Californium.
solveit 7y ago
I'm sure they exist, but there are no cases involving kilograms of Californium since there exist maybe ten grams of the stuff in the entire world.
- mehrdadn 7y ago
  Ten grams in the entire world? I see photos of what is claimed to be solid californium here... is that fake: http://www.chemistrylearner.com/californium.html http://www.chemistrylearner.com/californium.html
  - petschge 7y ago
    The image labeled "Californium bullet" actually shows laboratory neutron sources that contain 5 mg of Californium. The rest of the "bullet" is actually a stainless steel casing. The metal shaving further down the page are most likely microscopic, but as no length scale is given it is hard to estimate the mass.
    - ars 7y ago
      That website also claims Californium is used to make jewelry. Personally I have my doubts about that
- atemerev 7y ago
  Of course. Here I was talking about HEU/Pu.

foobarian 7y ago

> a whopping 1.4 kilograms (3.1 pounds) of a substance, believed to be Californium That's preposterous. Californium is not naturally occurring and costs tens of $M per gram to produce. Anyone who paid attention in high school should see big flashing alarms when reading a claim like that.

ars 7y ago
That much Californium in one place would probably go critical anyway. It might not explode, but it would glow and evaporate rather quickly.
- petschge 7y ago
  Critical mass of Cf-249 is 6kg, of Cf-251 5.46kg and of Cf-252 is 2.73kg. So no it would not go critical. 1.4 kg of Cf-252 would however emit something like 4e15 neutrons per second and 1.2kW (I first thought it was 700kW) of decay heat. Glowing and evaporation would be rather likely.
  - LeifCarrotson 7y ago
    700 kW emitted by a grapefruit-sized object will be a white-hot, rapidly-expanding gas cloud. Maybe it's not a nuke, but I don't know that your decay heat math is correct...half a critical mass of uranium or plutonium is slightly above room temp, not something that violently disintegrates. Is Cf252 different?
    - petschge 7y ago
      You are right, the 700kW was wrong. The calculation I did was as follows (and I will point out the mistake I made): 1.4 kg is 1.4e9 micrograms and as per [1] "one microgram emits 170 million neutrons per minute" will emit 1.4e9 * 1.7e8 / 60 = 4e15 neutrons per second. Decays of Cf-252 have a high neutron multiplicity, about 3.7 per decay, so the neutron came from 1.1e15 decays per second. Most of those (> 95%) came from the decat Cf-252 -> Cm-248. The masses of those two isotopes is 252.081626 and 248.072349 atomic mass units respectively, as per [2] and [3]. An alpha nucleus of 4.001506179127 u is also produced. (If forgot about that one, vaastly overestimating the decay heat.) A mass loss of 7.77e-3 u is equivalent to the release of 7.77e-3 * 0.9314941 GeV / u = 7.2 MeV. Each MeV is 1.60e-13 J. So in total we get 1.1e15 decays per second * 7.2 MeV per decay * 1.60e-13 J / MeV = 1.2 J/s = 1.2 kW. If you forget that the alpha nucleus exists you over estimate the mass loss by a factor 500 and get a decay power of 700kW... [1] http://nuclearweaponarchive.org/Nwfaq/Nfaq6.html#nfaq6.2 http://nuclearweaponarchive.org/Nwfaq/Nfaq6.html#nfaq6.2 [2] https://en.wikipedia.org/wiki/Isotopes_of_californium https://en.wikipedia.org/wiki/Isotopes_of_californium [3] https://en.wikipedia.org/wiki/Isotopes_of_curium https://en.wikipedia.org/wiki/Isotopes_of_curium

gridlockd 7y ago

Quoting the source of that story: "According to Monday's NTV article, the suspects were reportedly in possession of a cache of Californium weighing 1.441 kilograms that they planned to sell for $72 million on the black market." So, back in 2018, suspects were trying to sell 1.4 kg of a substance claimed to be Californium for $72 million. Now, in 2019, suspects were trying to sell a mere 18.1 grams of a substance claimed to be Californium, again, for $72 million. I am trying to imagine a gang of schmucks still trying to sell baking soda as Californium but now they adjusted the price to be more realistic.