Atomic Number: 55
Atomic Weight: 132.90543
Element Type: Alkali Metal
Crystal Structure: Cubic Face Centered
Melting Point: 28.44°C = 83.192°F = 301.59
Boiling Point: 671.0°C = 1239.8°F = 944.15
Critical Temp: °C = °F = K
Atomic Radius: 3.34 Å (Å = Angstrom =
Covalent Radius: 2.35 Å
(L. caesius, sky blue) Cesium was discovered spectroscopically
by Bunsen and Kirchhoffin 1860 in mineral water from Durkheim.
Cesium, an alkali metal, occurs in lepidolite, pollucte
(a hydrated silicate ofaluminum and cesium), and in other
sources. One of the world's richest sources of cesiumis
located at Bernic Lake, Manitoba. The deposits are estimated
to contain 300,000 tons ofpollucite, averaging 20% cesium.
It can be isolated by elecytrolysis of the fused cyanide
and by a number of othermethods. Very pure, gas-free cesium
can be prepared by thermal decomposition of cesiumazide.