Barium hydroxide, it absorbs very little CO in aqueous solutions and is therefore insensitive to atmospheric fluctuations. This property is used in calibrating pH equipment. Volatile barium compounds burn with a green to pale green flame, which is an efficient test to detect a barium compound. The color results from spectral lines at 455.4, 493.4, 553.6, and 611.1 nm. Organobarium compounds are a growing field of knowledge: recently discovered are dialkylbariums and alkylhalobariums. Barium found in the Earth's crust is a mixture of seven primordial nuclides, barium-130, 132, and 134 through 138. Barium-130 undergoes very slow radioactive decay to xenon-130 by
Barium sulfate casting of copper anode plates. The anode plates are cast in copper molds, so to avoid the contact of the liquid copper and the solid copper mold, a solution of barium sulfate in water is used as a coating material on the mold surface. Thus when the liquid copper solidifies in form of an anode plate it can be easily released from its mold. Barium sulfate is sometimes used (or else PTFE) to coat the interior of integrating spheres due to the high reflectance of the material and near Lambertian characteristics. Almost all of the barium consumed commercially is obtained