A gold Nobel Prize medal awarded to a founding radiochemist is expected to sell for thousands of pounds at auction.
Hungarian scientist George de Hevesy was awarded the Nobel Prize in 1943 for his work developing isotopes as tracers in the study of chemical processes.
His accolade, together with three other medals, is estimated to fetch between £120,000 and £150,000 when it is auctioned by Morton & Eden in London on November 23.
The lot will also include a Royal Society's Copley medal, Royal College of Physicians' Baly medal and Atoms for Peace Award.
David Kirk, of Morton & Eden, said: "George de Hevesy's work and achievements have led, in particular, to enormous advances in radiobiology, medical research and clinical diagnosis, including XRF, and not surprisingly he was recognised with numerous accolades and honours during his lifetime.
"The medals have remained in Hevesy's family until now and it is a huge privilege to be able to offer these medals to be appreciated by a wider audience."
Mr Hevesy also concealed two other Nobel Prize medals, awarded to fellow scientists, from capture by the Nazis during the Second World War by dissolving them in liquid.
After the war, he was able to reconstitute the gold and the medals were remade and re-awarded to their original recipients.