Barium-138 is the most abundant of the stable isotopes of the element. Its half-life is four x 1021 years, and its mass numbers range from 114 to 153. However, it is not a naturally occurring free element, and the only way to obtain it is by mining it.

The element is a member of group 2 of the periodic table. As such, it combines with other elements. For instance, it is an alloyed metal with aluminum and silicon. Other chemicals that combine with it include lead, tin, and zinc.

It is a soft silver-white metal with a density of about half that of iron. It is used as a scavenger in vacuum tubes, and as an additive in cast iron and steel. In addition, it is a component in spark-plug electrodes.

Barite is found in large deposits in China, Germany, Morocco, and the US. Most of the barite is mined in China.

Barium sulfate, or BaTeO4, is insoluble in water. It is also endothermic. Soluble barium compounds are toxic to mammals. When barium sulfate is mixed with water, a protective layer of sulfuric acid forms.

This protective layer prevents further reaction. Once a barium oxide passivation layer has formed on the surface of the barium, further reactions are inhibited.

Barium is one of the most reactive metals in the periodic table, and it reacts easily with oxygen. Besides oxidizing, it is also highly reactive with alcohol.

Barium has a green flame when heated, and it is a light metallic element. It is a member of the alkali earth metals.