Garnet

Al_1.28Ca_2.43Mn_1.29O₁₂Si₃

Arni, R.Langer, K.Tillmanns, E.

Physics and Chemistry of Minerals (1985) 12, 279-282

a=11.867Å   b=11.867Å   c=11.867Å

α=90°   β=90°   γ=90°