Barium

Barium (Ba, atomic number 56) is a soft, silvery-white alkaline earth metal in Group 2 of the periodic table, immediately below calcium and strontium, and the heaviest of the common alkaline earth metals. With a density of 3.62 g/cm³ and a melting point of 727 °C, barium is softer than most structural metals (Mohs 1.25) and highly reactive — it oxidises rapidly in air, reacts vigorously with water to release hydrogen, and ignites spontaneously when finely divided. For this reason, it is stored under inert oil or anhydrous mineral spirits and handled under inert atmosphere. Its body-centerd cubic (BCC) crystal structure is typical of Group 2 metals and gives barium high symmetry but low mechanical strength. Barium's most distinctive property is its exceptional X-ray opacity, arising from its large atomic number (Z = 56) and high electron density.

The dominant industrial use of barium is as barium sulfate (BaSO₄, barite), consumed in vast quantities as a weighting agent in oil and gas drilling fluids. Barite's high density (4.48 g/cm³), chemical inertness, and non-toxicity make it the preferred additive for increasing drilling mud density to control wellbore pressure during hydrocarbon extraction — global consumption exceeds 8 million tonnes per year. In medicine, barium sulfate suspension is the standard oral contrast agent for gastrointestinal fluoroscopy and CT imaging, exploiting its extreme X-ray opacity (µ/ρ ~10 cm²/g at diagnostic X-ray energies) and insolubility in body fluids. The compound barium titanate (BaTiO₃) is a landmark ferroelectric ceramic, and the basis of virtually all multilayer ceramic capacitors (MLCCs), piezoelectric transducers, and electro-optic devices.

In advanced materials and quantum technology, barium has become unexpectedly prominent. Yttrium barium copper oxide (YBCO, YBa₂Cu₃O₇₋ₓ) was the first material to exhibit high-temperature superconductivity above liquid nitrogen temperature (Tc ~93 K), revolutionising superconductor research from 1987 onward. Barium isotopes — particularly ¹³⁷Ba⁺ and ¹³³Ba⁺ — are leading candidates for trapped-ion quantum computing platforms, with long coherence times and favorable optical transitions accessible by commercially available laser systems. Barium ferrite (BaFe₁₂O₁₉) is a hard magnetic material used in permanent magnets, recording media, and microwave absorbers. Barium oxide (BaO) and barium compounds serve as getter materials in vacuum tubes and OLED encapsulation to scavenge oxygen and water vapour.

Goodfellow offers pure barium (Ba) products designed for use in both industrial processes and scientific research. One of its most prominent uses is in the production of barium sulfate (BaSO₄), which serves as a contrast agent in medical imaging techniques such as X-rays and CT scans. This compound's radiopacity makes it ideal for enhancing image clarity during diagnostic procedures. In the oil and gas industry, barium compounds are used as weighting agents in drilling fluids to stabilize wellbores during extraction processes. Additionally, barium finds applications in electronics manufacturing, particularly in vacuum tubes and cathode ray tubes (CRTs), where it acts as a getter material to remove residual gases. Advanced technologies benefiting from barium include energy storage systems like batteries and supercapacitors, where it contributes to improved performance and efficiency. Goodfellow's barium products enable researchers to explore new frontiers in materials science while supporting critical industrial applications that rely on its unique properties.