Aluminium borate

The basic borate, 3Al₂O₃.B₂O, was prepared by Ebelmen by strongly heating a mixture of alumina and borax. It forms colourless, orthorhombic crystals (a:b:c = 0.974:1:0.679) of density 3.0. The precipitates obtained by mixing alkali borate solutions with solutions of aluminium salts are also basic aluminium borates.