Tumchaite

H₄Na₂O₁₃Si₄Sn_0.2Zr_0.8

Subbotin, V. V.Merlino, S.Pushcharovsky, D. Y.Pakhomovsky, Y. A.Ferro, O.Bogdanova, A. N.Voloshin, A. V.Sorokhtina, N. V.Zubkova, N. V.

American Mineralogist (2000) 85, 1516-1520

a=9.144Å   b=8.818Å   c=7.537Å

α=90°   β=113.22°   γ=90°