C2CaMgO6
Miser, D. E.Swinnea, J. S.Steinfink, H.
American Mineralogist (1987) 72, 188-193
a=4.811Å b=4.811Å c=16.047Å
α=90° β=90° γ=120°
Ca0.052Mg1.948O6Si2
Carlson, W. D.Swinnea, J. S.Miser, D. E.
American Mineralogist (1988) 73, 1255-1263
a=18.280Å b=8.834Å c=5.197Å
α=90° β=90° γ=90°