Ununseptium, or Element 117, does not exist in nature but is man made.
“Physicists at GSI Helmholtz Center for Heavy Ion Research in Darmstadt, Germany, have used calcium-ion beams and radioactive berkelium-249 to produce two atoms of the element with atomic number 117, which bears the temporary name Ununseptium (one-one-seven in Latin).” – From SciNews article
It was first detected in 2010, but now subsequent creations have “confirmed” its existence.
Electron Shell of Ununseptium. Image Credit: Wikicommons)
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