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World Uranium & Thorium Resources


II. Uranium Resources
The USGS map of Uranium Concentrations shows how comprehensive their search was, finding a substantial resource of 5.6Mt. In the 1950s the government issued free Geiger counters to would be explorers. The USA currently imports 95% of its Uranium with most of its mines inactive. Other countries have not been so meticulous but every mining geologist knows what to look for.

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The IAEA, OECD, and NEA periodically publish their authoritative Red Book analysis on mineable Uranium [IAEA, 2011]. This lists “Found” mines and reserves, “Reasonably Assured Resources” (RAR) in similar geologies, “Inferred Resources” if we look harder, and “Prognosticated” and “Speculative” resources in unexplored regions. The 40+ Reporting countries also estimate the mining costs per kg of Uranium from their sources. Total production is currently 58,000t/yr. Coal mines now produce ~1Bnt/yr.

Our Chart below shows the world totals for each cost range and Uncertainty level. The “Speculative” resources are the highest. There is a total of only 161,000t U-235 in mined Uranium as indicated by the red caps on each stack. It is not necessary or cost effective to extract all the U-235 from a batch of Uranium. Instead, enrichment is stopped with ~0.2% of U-235 in the tailings, which are set aside and called “Depleted Uranium” (DU). Thus, only ~0.5%, or 115,000 t, is available from the ores for fresh reactor fuel.


The IAEA Red Book completes the tally of possible fuels with some reported resources of 6MT of the non-fissile metal, Thorium. It has a single isotope, Thorium-232 , and like U-238 can breed another fissile Uranium isotope, U-233, which has long disappeared from the planet. A reactor is the only way to make tonnes of U-233. Just the declared resource would be good for 6 million GW-e reactor years, though 60 Mt might be found.
It might appear that there are lots of fissile fuels, but only U-235 lives on in ores. The other fissile isotopes, U-233 and Pu-239, must all be made in reactors. The IAEA has accounted for the only natural resources, Uranium and Thorium.

IAEA 2011 Red Book, latest edition:
McNamara, 2006: Uranium – What is to be done?


  • 1 Why does the US import 95% of its Uranium when it has its own large resources?

  • 2. The NAVAJO Indians oppose Uranium mining on their land. When might this resource be really needed?

  • 3 If 40 countries have their own Uranium does this lead inevitably to widespread growth of nuclear weapons?

  • 4. Is Depleted Uranium a waste product or not?

  • 5 It looks like U235 is only good for 115,000 reactor years but Thorium could be good for 6 million reactor years. Why is this?

GRAND CANYON URANIUM & Australian Resources
Anti-nuclear Australia is major Uranium and coal source. Leave Colorado alone for centuries.
Iran needs fuel enriched with natural U-235 - negotiating with USA
Thorium takes 27 days to decay to U-233 after absorbing a Neutron.