Dravite

Al₆B₃Ca_0.05F_0.038Fe_0.231H_3.42K_0.01Mg_2.769Na_0.711O_30.962Si₆

Bacik, P.Uher, P.Ertl, A.Jonsson, E.Nysten, P.Kanicky, V.Vaculovic, T.

The Canadian Mineralogist (2012) 50, 825-841

a=15.921Å   b=15.921Å   c=7.175Å

α=90°   β=90°   γ=120°