barium

Barium is a chemical element with the symbol Ba and atomic number 56. It is an alkaline earth metal that is soft and highly reactive. In its pure form it is a pale, silvery-white metal that tarnishes readily in air and reacts with water and acids.

Natural occurrence and minerals: Barium occurs only in mineral form and is extracted from minerals such as barite (barium sulfate, BaSO4) and witherite (barium carbonate, BaCO3). Barite is the principal ore and is mined in various regions around the world. The element is typically recovered by processing these minerals into soluble salts, which are then converted to the desired compound or metal.

Production and compounds: Industrial barium production involves converting baryte into soluble barium salts followed by reduction or electrolysis to obtain metal or by producing useful compounds directly. Barium compounds are widely used in various applications, often in stable, insoluble forms that reduce toxicity concerns.

Applications: Barite is a major drilling fluid additive in the oil and gas industry due to its high density and chemical inertness. Barium sulfate is also used as a radiopaque contrast agent for X-ray imaging, because it is insoluble and not absorbed by the body. Barium compounds are employed in glassmaking and ceramics, and barium titanate is important in electronics as a ceramic dielectric. In fireworks, barium salts such as barium nitrate provide a characteristic green flame.

Safety and health: Soluble barium compounds are toxic if ingested or inhaled and can cause serious health effects. Barium sulfate, being insoluble, is relatively non-toxic and used medically under controlled conditions. Handling requires appropriate safety precautions to avoid exposure to soluble salts.

History: Barium was identified in the late 18th century by Carl Wilhelm Scheele and isolated by Humphry Davy in 1808 through electrolysis of a barium compound, earning its name from barys, Greek for heavy.