Friedrichbeckeite

Be_1.821K_0.926Mg_2.793Mn_0.386Na_0.772O₃₀Si₁₂

Lengauer, C. L.Hrauda, N.Kolitsch, U.Krickl, R.Tillmanns, E.

Mineralogy and Petrology (2009) 96, 221-232

a=9.970Å   b=9.970Å   c=14.130Å

α=90°   β=90°   γ=120°