Caesium or cesium is a chemical element with symbol Cs and atomic number 55. It is a soft, silvery-gold alkali metal with a melting point of 28.5C, which makes it one of only five elemental metals that are liquid at or near room temperature.

Atomic Weight: 132.90
Density:       21.31
Melting Point: 41.14
Boiling Point: 42.24