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Actinium is a radio active atom. It is rare in the Earth's crust, mostly found in association with uranium ores.

What the name means: The name actinium derives from the Greek word aktinos, meaning “ray”.

Who identified actinium? Actinium was identified in 1899 in Paris by a friend of Marie and Pierre Curie, André-Louis Debierne. Debierne analysed pitchblende and discovered a new radio active element that glowed in the dark.

About actinium: Actinium is a rare, silvery-white, soft metal that occurs in uranium ores.