(From the Greek barys, "heavy") A silver-white, slightly malleable, metallic chemical element, one of the alkaline-earth metals, found as a carbonate or sulfate and used in alloys.

Symbol: Ba
Atomic number: 56
Atomic weight: 137.327
Density (at room temperature and pressure): 3.51 g/cc
Melting point: 730°C
Boiling point: 1,897°C
Valence: +2
Ground state electron configuration: [Xe]6s2