XRD diffractograms of tin chloride and zinc nitrate samples: q, quartz; p, portlandite (Ca(OH)₂); a, α-C₂SH (Ca₂(SiO₄)H₂O); t, tobermorite-11Å (Ca₅Si₆(OH)₁₈); b, brownmillerite (Ca₂FeAl₂O₅)