What are the origins of the word Caesium ?
The word Caesium originates from the Latin word 'caesius' which means "sky blue" from the bright blue lines in its spectrum.

Facts about the Classification of the Element Cesium
Cesium is classified as an "Alkali Metal" and located in Group 1 elements of the Periodic Table. An Element classified as an Alkali Metal is a very reactive metal that does not occur freely in nature. Alkali metals are soft, malleable, ductile, and are good conductors of heat and electricity.

Brief Facts about the Discovery and History of the Element Cesium
Cesium was discovered by Fustov Kirchoff and Robert Bunsen in 1860 from mineral water found in Durkheim, Germany. It was the first element discovered by spectrum analysis.

Occurrence of the element Cesium
Obtained from pollucite and lepidolite

Common Uses of Cesium
Atomic clocks
Removes air traces in vacuum tubes
Ion propulsion systems
Medical
Photoelectric cells
Cesium vapor
Magnetometer

The Properties of the Element Cesium
Name of Element : Cesium
Symbol of Element : Cs
Atomic Number of Cesium : 55
Atomic Mass: 132.90546 amu
Melting Point: 28.5 °C - 301.65 °K
Boiling Point: 678.4 °C - 951.55005 °K
Number of Protons/Electrons in Cesium : 55
Number of Neutrons in Cesium : 78
Crystal Structure: Cubic
Density @ 293 K: 1.873 g/cm3
Color of Cesium : silvery-white