how is barium classified
Barium is a chemical element with symbol Ba and atomic number 56. It is the fifth element in Group 2, a soft silvery metallic alkaline earth metal. Because of its high chemical reactivity, barium is never found in nature as a free element. The hydroxide, known in pre-modern history as baryta, does not occur as a mineral, but can be prepared by heating barium carbonate.
1 Barium follow through examinations are used to study the small intestine.  Enteroclysis also called small bowel enema is a Barium X-ray examination used to display individual loops of the small intestine by intubating the jejunum with a small tube and administering Barium sulfate followed by methylcellulose or air.