M. Schmidt et al., THE NOVEL BINUCLEAR HYDROXYBERYLLATE SPECIES [BE-2(OH)(7)](3-) AND THE HYDROXIDE HYDRATE ANION [H3O2](-) AS COMPONENTS OF BERYLLATE EQUILIBRIA, Inorganic chemistry, 37(14), 1998, pp. 3452
The precipitate obtained from sodium beryllate solutions with calcium
ions is not the presumed calcium tetrahydroxyberyllate hydrate Ca[Be(O
H)(4)](H2O)(n), but a heptahydroxydiberyllate hydroxide hydrate Ca-2[B
e-2(OH)(7)][HO-H-OH](H2O)(2).