This is the Rare 1917 American Museum of Atomic Energy Mercury Dime as photographed. The Museum of Atomic Energy has been irradiating silver dimes, using a neutron flux, allowing visitors of the museum to see the radioactivity through a Geiger counter when it was done. After, they would be encased as seen above for safety reasons.
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Rare 1917 American Museum of Atomic Energy Mercury Dime - Neutron Irradiated Mercury Dime 1917 - Museum of Atomic Energy Relic 1917