Rhodonite

Ca_0.6Mg_0.86Mn_3.54O₁₅Si₅

Peacor, D. R.Essene, E. J.Brown, P. E.Winter, G. A.

American Mineralogist (1978) 63, 1137-1142

a=9.797Å   b=10.497Å   c=12.185Å

α=108.55°   β=103.02°   γ=82.49°