Barium Selenite, BaSeO₃

Barium Selenite, BaSeO₃, is obtained by precipitation from solutions of barium nitrate and sodium selenite. Stable, microscopic, prismatic crystals are formed, containing 1 molecule of water, BaSeO₃.H₂O.

An acid salt, BaSe₂O₅, is obtained by evaporating a solution of barium carbonate in excess of selenious acid. It is only slightly soluble.