Represented by the symbol ‘Ba’, Barium is a group 2 element in the periodic table with atomic number 56.
Barium is a dense alkaline earth metal that occurs naturally in ore deposits and makes up 0.05% of the Earth’s crust (Genter 2001). Barium and its compounds may be found in nature or produced industrially for various uses.
It is a silvery-white metal that can be found in the environment, where it exists naturally. It occurs combined with other chemicals, such as carbon, oxygen, and sulfur.
It is very light and its density is half of that of iron.
Barium oxidizes in air, reacts vigorously with water to form the hydroxide, liberating hydrogen. It reacts with almost all the non-metals, forming often poisoning compounds.
Barium carbonate is widely used in the ceramics industry as an ingredient in glazes. It acts as a flux, a matting and crystallizing agent and combines with certain colouring oxides to produce unique colours not easily attainable by other means. Its use is somewhat controversial since some claim that it can leach from glazes into food and drink. To provide a safe means of use, BaO is often used in fritted form.
In the brick, tile, earthenware and pottery industries barium carbonate is added to clays to precipitate soluble salts (calcium sulfate and magnesium sulfate) that cause efflorescence.