Pollucite is acid-leached, and Cs is separated from Rb by fractional crystallization of Cs alum or by ion exchange; metallic Cs comes from reducing CsCl with Ca under vacuum.
Research Elements Cs · atomic number 55 Alkali metal · period 6, group 1 [Xe] 6s1 Shells: 2, 8, 18, 18, 8, 1 Valence electrons: 1 in the outer shell (6s1) Green dots are the outer shell's s and p electrons. Softer green dots are the d electrons of transition metals, and the d and f electrons of lanthanides and actinides: they often take part in bonding, but not always. Grey dots are the core. Ground-state configuration from the NIST Atomic Spectra Database (A. Kramida, Yu. Ralchenko, J. Reader and the NIST ASD Team). Abundance is the mole fraction of the element found as that isotope on Earth; digits in parentheses are the uncertainty in the last digits. Masses and abundances from NIST, Atomic Weights and Isotopic Compositions (J. S. Coursey, D. J. Schwab, J. J. Tsai and R. A. Dragoset, National Institute of Standards and Technology).Cesium
Electrons
How it's obtained
Natural isotopes
Isotope Relative atomic mass Abundance 133Cs 132.9054519610(80) 1