ionium
noun
io·ni·um
ī-ˈō-nē-əm 
: a natural radioactive isotope of thorium having a mass number of 230
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Rona set to work isolating a potential new element called ionium.
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New York Times, 28 Aug. 2019
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New York Times, 28 Aug. 2019
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“Ionium.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/ionium. Accessed 31 Jul. 2025.
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ionium
noun
io·ni·um
ī-ˈō-nē-əm
: a natural radioactive isotope of thorium having a mass number of 230
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