The reaction of elemental barium, gallium and either bismuth or antimony with small amounts of barium peroxide yields yellow platelet-shaped crystals of Ba 9 [GaO 4 ] 3 Sb ( 1 ) and orange platelet-shaped crystals of Ba 9 [GaO 4 ] 3 Bi ( 2 ), respectively. Using arsenic instead of bismuth or antimony, black metallic shining crystals of Ba 2 [GaO 2 As] ( 3 ) are obtained. The crystals of these compounds are air-sensitive and have been characterized by single crystal X-ray diffraction and energy dispersive X-ray fluorescence spectroscopy. 1 and 2 contain tetrahedral [GaO 4 ] 5─ units and isolated Sb 3– and Bi 3– ions coordinated solely by Ba 2+ -ions in icosahedral and cuboctahedral fashion. 3 is built of [GaO 2 As 2/2 ] 4─ tetrahedra, which are linked via the As atoms to infinite chains. This polyanion can be perceived as a typical Zintl anion, which is partially oxidized.