Facts about the Classification of the Element Actinium
Actinium classified as an element in the Actinide series as one of the "Rare Earth Elements" which can located in Group 3 elements of the Periodic Table and in the 6th and 7th periods. The Rare Earth Elements are of the Lanthanide and Actinide series. Most of the elements in the Actinide series are synthetic or man-made.

Brief Facts about the Discovery and History of the Element Actinium
Actinium was discovered by Andre-Louis Debierne in France in 1899. Friedrich Otto Giesel independently discovered actinium in 1902.

Occurrence of Actinium
Actinium is found in trace amounts in uranium ore

Associated Uses of the element Actinium
A neutron source
Medicine

The Properties of the Element Actinium
Symbol of Element : Ac
Atomic Number of Actinium : 89
Atomic Mass: (227.0) amu
Melting Point: 1050.0 °C - 1323.15 °K
Boiling Point: 3200.0 °C - 3473.15 °K
Number of Protons/Electrons in Actinium : 89
Number of Neutrons in Actinium : 138
Crystal Structure: Cubic
Density @ 293 K: 10.07 g/cm3
Color of Actinium : Silvery