All About Uranium

I just finished an excellent book called Uranium, by Tom Zoellner. That's right, a whole book just about uranium!

I am always interested in how people, places and things are inter-related. One place that provides more than its share of connections is St. Joachimsthal, a silver mining town in Bohemia. A popular product of St. Joachimsthal in the 16th century was large silver coins that were used throughout Europe. These were commonly called "Joachimsthalers", which was shortened to "thaler", and is the basis of our English word "dollar".

Uranium ore was first discovered in the silver mines here in the late 15th century. The miners named this unusual material pechblende. "Pech" is German for "pitch", or tar, which is what the ore looked like. "Pech" can also mean "bad luck". A clever double entendre, since the tarry material slowed down the miners' extraction of silver. (Blende is a general term for a mineral with a dull luster.)

Almost 300 years passed before anyone bothered to study the mining waste more closely. But in 1789, German pharmacist Martin Klaproth isolated a new element from the pitchblende that he named uranium. Still, not much use was found for pitchblende other than as a pigment for glass.

Another century passed before Marie and Pierre Curie used pitchblende, from this same mine in St. Joachimsthal, to isolate another new element that would make them famous, radium.

St. Joachimsthal soon became a popular spa destination, with visitors believing the radiation to be good for their health. One of the visitors to this spa was a young J. Robert Oppenheimer, who was intrigued by the geology of the mines. Oppenheimer would later harness uranium's power as scientific director of the Manhattan Project.

But the uranium used to make the first atomic bombs did not come from St. Joachimsthal. By then, that part of Bohemia (in Czechoslovakia) had been annexed by Hitler. Fortunately, the Americans were quicker than the Nazis in solving the engineering challenges involved in building the bomb. And fortunately, an alternative source of uranium had since been found in the Belgian Congo.

Although Hitler was not successful in exploiting the uranium from St. Joachimsthal, Stalin was. The Soviet Union took control of Czechoslovakia after World War II, and St. Joachimsthal supplied the uranium that helped escalate the Cold War.