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New data on the isomorphism of extra-framework components (including chromophores) in two- and multilayer minerals belonging to the cancrinite and sodalite groups, are obtained using chemical and single-crystal X-ray diffraction data as well as infrared, Raman, ESR, UV–Vis–near IR absorption and photoluminescence spectroscopy methods. It is shown that the blue color of these minerals may be due to CO₃^•− or S₃^•− radical anions, whereas yellow and pink shadings are typically due to the presence of S₂^•− radical anions and S₄^•− or S₄, respectively. Two kyanoxalite varieties are distinguished: (1) with predominantly acid oxalate groups and (2) predominantly neutral oxalate groups. Zundel cation H₅O₂+ and CO₂ molecules are shown to be typical impurities in nosean. The Zundel cation is also detected in kyanoxalite and in the 12-layer, cancrinite-related mineral marinellite. Wide isomorphic series involving substitutions of SO₄⁻ for SO₃²⁻ and CO₃²⁻, as well as OH⁻ for H₂O and F⁻, are common for eight-layer, cancrinite-group minerals with an afghanite-type framework.