Orthoclase Chao S, Hargreaves A, Taylor W Mineralogical Magazine 25 (1940) 498-512 The structure of orthoclase. _cod_database_code 1011205 _database_code_amcsd 0018075 8.6 13.02 7.22 90 116.05 90 C2/m atom x y z occ K1 .2917 0 .1389 Si1 .7097 .1167 .347 Al2 .0097 .1875 .225 .5 Si2 .0097 .1875 .225 .5 O1 0 .1528 0 O2 .6667 0 .3028 O3 .8194 .1528 .2278 O4 .0417 .3167 .2611 O5 .1722 .1278 .4167