data_global _chemical_name_mineral 'Forsterite' loop_ _publ_author_name 'Birle J D' 'Gibbs G V' 'Moore P B' 'Smith J V' _journal_name_full 'American Mineralogist' _journal_volume 53 _journal_year 1968 _journal_page_first 807 _journal_page_last 824 _publ_section_title ; Crystal structures of natural olivines Note: variety hyalosiderite ; _database_code_amcsd 0000172 _chemical_formula_sum 'Mg1.07 Fe.912 Mn.012 Ca.004 Si O4' _cell_length_a 4.785 _cell_length_b 10.325 _cell_length_c 6.038 _cell_angle_alpha 90 _cell_angle_beta 90 _cell_angle_gamma 90 _cell_volume 298.308 _exptl_crystal_density_diffrn 3.782 _symmetry_space_group_name_H-M 'P b n m' loop_ _space_group_symop_operation_xyz 'x,y,z' 'x,y,1/2-z' '-x,-y,1/2+z' '1/2+x,1/2-y,1/2+z' '1/2-x,1/2+y,1/2-z' '1/2-x,1/2+y,z' '1/2+x,1/2-y,-z' '-x,-y,-z' loop_ _atom_site_label _atom_site_fract_x _atom_site_fract_y _atom_site_fract_z _atom_site_occupancy _atom_site_U_iso_or_equiv Mg1 0.00000 0.00000 0.00000 0.53500 0.00405 Fe1 0.00000 0.00000 0.00000 0.45600 0.00405 Mn1 0.00000 0.00000 0.00000 0.00600 0.00405 Ca1 0.00000 0.00000 0.00000 0.00200 0.00405 Mg2 0.98598 0.27880 0.25000 0.53500 0.00469 Fe2 0.98598 0.27880 0.25000 0.45600 0.00469 Mn2 0.98598 0.27880 0.25000 0.00600 0.00469 Ca2 0.98598 0.27880 0.25000 0.00200 0.00469 Si 0.42843 0.09587 0.25000 1.00000 0.00241 O1 0.76566 0.09430 0.25000 1.00000 0.00507 O2 0.21642 0.45084 0.25000 1.00000 0.00709 O3 0.28264 0.16370 0.03435 1.00000 0.00633