Physical data, chemical properties, health and environmental effects.

History, properties, and uses.

Data tables and historic information.

Source, biological role, physical information, and key isotopes.

Basic physical and historical information.

Full text of the monograph by J. G. Cuninghame (Atomic Energy Research Establishment, Harwell, Didcot, Berkshire, England). [PDF]

Basic information, atomic structure, and isotopes.

Electronic, thermal, and steric data along with an isotope table.

Thermal properties, ionisation energies, and reduction potentials.