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Al_7.419B₃Fe_1.581H_3.58O₃₁Si₆

Kahlenberg, V.Velickov, B.

European Journal of Mineralogy (2000) 12, 947-953

a=15.964Å   b=15.964Å   c=7.119Å

α=90°   β=90°   γ=120°