Entry
The discovery of radium — The announcement to the Académie des sciences, 1898
Pitchblende was more radioactive than the uranium it contained: something else must be hiding in it. After polonium in July, a note signed by both Curies and Gustave Bémont announced a second substance, nine hundred times more active than uranium. Three more years were needed to isolate it, and it killed the woman who had named it. (Editorial synthesis)
The discovery of radium ended in the identification of the elements polonium and radium. (source: Encyclopædia Britannica)
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