Sverigeite

Be₂HMg_0.63Mn_1.37NaO₁₃Si₃Sn

Rouse, R. C.Peacor, D. R.Metz, G. W.

American Mineralogist (1989) 74, 1343-1350

a=10.815Å   b=13.273Å   c=6.818Å

α=90°   β=90°   γ=90°