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.
This looked like big money to Sharp. Uranium is the mother product of radium — the radioactive wonder mineral that had been recently isolated by Pierre Curie and Marie Curie. A Belgian company recruited a native workforce and dug a terraced pit that chugged out radium for more than 20 years before the market soured and the pit was allowed to fill up with dirty, gray water. But when British scientists learned in the 1930s of experiments in chain reactions of uranium that could be forced to explode under the right conditions, they began making discreet inquires about spare barrels of uranium — previously considered nearly worthless — from Shinkolobwe.