When the Nazis invaded Denmark in 1940, Niels Bohr was in possession of two of the Nobel Prize’s gold medals for Physics that had previously been sent to him for safe-keeping. Here’s what he did to hide them — and how the Nobel prizes were brought back again.

io9’s comment of the day comes from commenter s. pisaster, who reminded of us the importance of this chemistry story in history:

Niels Bohr. He was instrumental in getting numerous scientists away form Nazi Germany, himself escaped capture by Nazis after they invaded Denmark, and, my personal favorite detail, hid the nobel medals of two Danish scientists from said Nazis by dissolving them in nitro-hydrochloric acid (the gold was recovered and recast after the war).


Bohr did, indeed, dissolve and later recast the medals — a solution that becomes even more impressive when you consider that one of gold’s most distinctive properties is how difficult it is to dissolve.

Robert Krulwich covered the whole tale for NPR, describing how Bohr held the two Nobel Prize medals for Physics — one belonging to 1914 winner, Max von Laue and the other to 1925 winner, James Franck — until the day the of the Nazi invasion of Denmark. Then, with the help of a chemist in his lab, Georgy de Hevesy, they managed to painstakingly dissolve the medals into a solution and hide the beaker in plain sight.

It was an exceptionally clever means of hiding the medals, but even cleverer is what de Hevesy did next:

Back in Denmark, de Hevesy did a remarkable thing. He reversed the chemistry, precipitated out the gold and then, around January, 1950, sent the raw metal back to the Swedish Academy in Stockholm. The Nobel Foundation then recast the prizes using the original gold and re-presented them to Mr. Laue and Mr. Franck in 1952. Professor Frank, we know, got his re-coined medal at a ceremony at the University of Chicago, on January 31, 1952.


Image: Nobel Prize for Physics / Nobel Prize Committee