Marie’s next idea, seemingly simple but brilliant, was to study the natural ores that contain uranium and thorium. She obtained samples from geological museums and found that of these ores, pitchblende was four to five times more active than was motivated by the amount of uranium. It was her hypothesis that a new element that was considerably more active than uranium was present in small amounts in the ore.
Marie and Pierre – A Fruitful Collaboration
Fascinating new vistas were opening up. Pierre gave up his research into crystals and symmetry in nature which he was deeply involved in and joined Marie in her project. They found that the strong activity came with the fractions containing bismuth or barium. When Marie continued her analysis of the bismuth fractions, she found that every time she managed to take away an amount of bismuth, a residue with greater activity was left. At the end of June 1898, they had a substance that was about 300 times more strongly active than uranium. In the work they published in July 1898, they write, “We thus believe that the substance that we have extracted from pitchblende contains a metal never known before, akin to bismuth in its analytic properties. If the existence of this new metal is confirmed, we suggest that it should be called polonium after the name of the country of origin of one of us.” It was also in this work that they used the term radioactivity for the first time. After another few months of work, the Curies informed the l’Académie des Sciences, on December 26, 1898, that they had demonstrated strong grounds for having come upon an additional very active substance that behaved chemically almost like pure barium. They suggested the name of radium for the new element.
Riswan E. Tarigan, Thinker, Motivator & Inspirator 
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