How is weapons-grade uranium-235 extracted out of uranium ore?
Uranium-235 is slightly lighter in mass than the remaining uranium ore. Separation techniques capitalize on this difference. For example, one method — gas centrifuge enrichment — spins gaseous uranium hexafluoride in cylinders, so the lighter uranium-235 moves toward the inner wall, where is it collected. (For more information, see the Wisconsin Project “Bomb Facts: How Nuclear Weapons are Made,” http://www.wisconsinproject.
