The US sourced uranium for the weapons used on Japan from Shinkolobwe; though the site is closed, locals mine illegally
One of the manifest ironies of the nuclear age is just how primitive it all is. A complicated war was brought to an end within a week by a pair of indiscriminate hammer blows. The logic behind the next 45 years of Cold War military strategy — hit us and we both die — was as simplistic as it was problematic. And driving everything was a bomb fashioned out of dirt.
A particular kind of dirt, of course, and one that required a lavish industrial process before it could be made into a fissile device. That dirt is uranium, and it lies all around the world in abundant quantities. A place where it was concentrated to levels of freakish purity is now just a curious footnote of the nuclear age, but at one time, it was treated with intense secrecy.
Shinkolobwe was a small settlement in the Katanga province of what was then the Belgian Congo. Its name refers to a particular kind of boiled apple that would leave a burn if it was squeezed. In 1915 a prospector, Robert Rich Sharp, was looking for geological signs of copper and heard stories about people rubbing a particular kind of colorful mud on their skin. He thought it might be copper, but what he found on the top of a short hill was uranium, which can oxidize with other minerals in a variety of bright colors.