Na2 Mg4 (Si6 O16 (O H)2)

H₂Mg₄Na₂O₁₈Si₆

Tateyama, H.Shimoda, S.Sudo, T.

Contributions to Mineralogy and Petrology (23,1969-) (1978) 66, 149-156

a=10.152Å   b=27.137Å   c=5.276Å

α=90°   β=106.97°   γ=90°