Fun uranium facts: during WWII, one method that the Manhattan Project used to refine uranium (i.e. separate U235 from natural uranium which is mostly non-fissile U238) relied on magnetism. A charged particle moving through a magnetic field experiences a force perpendicular to the direction of motion, which makes it follow a slightly curved path instead of a straight line. This force is the same for both U235 and U238 but since U235 weighs slightly less, its path is slightly more curved. By charging particles of natural uranium and shooting them through a powerful magnetic field, separate collectors can be set up to gather the U235 particles.

Creating the magnetic field required powerful electromagnets. Normally these would have used copper wire but copper was a valuable strategic metal needed for much of the other military hardware the US was producing, so the Manhattan Project "checked out" the United States' reserves of silver to build the magnets. For good measure, the electricity for the magnets came mostly from the hydroelectric dams built as part of the Tennessee Valley Authority projects of the 1930s (this is mainly why the Manhattan Project's uranium processing facilities were located in Oak Ridge). These dams were originally meant to power the production of aluminum, but the US had plenty of other sources for that.