Uranium
The dense fuel of nuclear power: a small, opaque market where mining, conversion and enrichment each carry separate supply risks.
Natural sources · Earth, gravity and atoms · No. 18
- US critical 2025
- HHI 2,319 · moderately concentrated
Congo's Shinkolobwe ore was nearly 70% uranium, against about 0.01% elsewhere, and it fuelled the Hiroshima bomb.
Chart: Illustration: Uranium
Where it comes from
Chart: Map of where it comes from
Uranium atoms were forged in exploding stars before the Earth existed. Kazakhstan pumps acid through underground sandstone to dissolve it, while Canada mines ultra-rich ore in the Athabasca Basin.
Three things to know
- Splitting heavy atoms releases millions of times more energy per kilogram than burning any chemical fuel.
- Australia holds the largest uranium resources yet mines only about 8% of world output.
- Utilities hoard fuel because an idle reactor is so costly: the US held about 42,000 tU at end-2024.
The journey
- 1 Ore bodySandstone, unconformity or breccia deposits
- 2 Leaching or millingAcid pumped through rock, or ore crushed
- 3 YellowcakeConcentrated U3O8 powder
- 4 Conversion, enrichmentTurned to UF6, U-235 share raised
- 5 Fuel assembliesPellets packed into reactor fuel