Forsterite Birle J D, Gibbs G V, Moore P B, Smith J V American Mineralogist 53 (1968) 807-824 Crystal structures of natural olivines Note: variety hyalosiderite _database_code_amcsd 0000172 4.785 10.325 6.038 90 90 90 Pbnm atom x y z occ Biso Mg1 0 0 0 .535 .32 Fe1 0 0 0 .456 .32 Mn1 0 0 0 .006 .32 Ca1 0 0 0 .002 .32 Mg2 .98598 .27880 .25 .535 .37 Fe2 .98598 .27880 .25 .456 .37 Mn2 .98598 .27880 .25 .006 .37 Ca2 .98598 .27880 .25 .002 .37 Si .42843 .09587 .25 .19 O1 .76566 .09430 .25 .40 O2 .21642 .45084 .25 .56 O3 .28264 .16370 .03435 .50