ionium

American  

[ahy-oh-nee-uhm] / aɪˈoʊ ni əm /

noun

Chemistry.

1. a naturally occurring radioactive isotope of thorium. Io; 90; 230.

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ionium British  

/ aɪˈəʊnɪəm /

noun

1.  Io.  obsolete a naturally occurring radioisotope of thorium with a mass number of 230

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Etymology

Origin of ionium

First recorded in 1905–10; ion + -ium

Example Sentences

Then crusty old Elias Loomis pioneered in devising the basis for modern weather maps and Bertram Boltwood discovered ionium.

From Time Magazine Archive

Uranium X1, then, would have an atomic weight of 234 and that of ionium would be 230.

From A Brief Account of Radio-activity by Venable, Francis Preston

Boltwood discovered in uranium minerals the presence of a body which he named ionium, and which is so similar to thorium that it cannot be separated from it.

From A Brief Account of Radio-activity by Venable, Francis Preston

Further, it became clear from the investigation of uranium minerals that radium, polonium, actinium, and ionium originated from uranium.

From A Brief Account of Radio-activity by Venable, Francis Preston

Ballon’s first samples gave uranium atoms with a fair representation of ionium and thorium.

From Astounding Stories of Super-Science, March 1930 by Bates, Harry