Crystal Structure of the Ba, Sr and Ca Triple Carbonate

Crystal structures of the co-precipitated triple carbonates of Ba, Sr and Ca were studied by x-ray powder method using an x-ray Geiger counter spectrometer. There exist three kinds of solid solutions : aragonite type crystal (λ-carbonate), calcite type crystal (β-carbonate) and vaterite type crystal (µ-carbonate); in the BaCO 3 -SrCO 3 -CaCO 3 system. The phase domains of these three crystal forms are affected some-what by the temperature at which the precipitation is carried out. The triple diagrams are obtained at two stages of precipitation temperatures.