Discovered by Andre Debierne in 1899 and independently by F. Giesel in 1902. Occurs naturally in association with uranium minerals.

Not found anywhere. Man made.

Used for Thermoelectric power. Power is generated by Heat, powered by Actinium.

Radium is 1,000,000 times more radioactive then plutonium. Actinium is 150 times more radioactive then Radium.