Fergusonite-(Y) Komkov A I Soviet Physics Crystallography 4 (1959) 796-800 The structure of natural fergusonite, and a polymorphic modification Locality: Ural Mountains, Russia _database_code_amcsd 0015538 5.16 5.16 10.89 90 90 90 I4_1/a atom x y z occ Y 0 0 .5 .85 Yb 0 0 .5 .15 Nb 0 0 0 O .185 .25 .092