Siderite Graf D L American Mineralogist 46 (1961) 1283-1316 Crystallographic tables for the rhombohedral carbonates Locality: synthetic _database_code_amcsd 0000101 4.6887 4.6887 15.373 90 90 120 R-3c atom x y z Fe 0 0 0 C 0 0 .25 O .2743 0 .25