Northupite Dal Negro A, Giuseppetti G, Tadini C Tschermaks Mineralogische und Petrographische Mitteilungen 22 (1975) 158-163 Refinement of the crystal structure of northupite: Na3Mg(CO3)2Cl Locality: Searles Lake, California, USA _database_code_amcsd 0015654 14.069 14.069 14.069 90 90 90 *Fd3 .125 .125 .125 atom x y z Biso B(1,1) B(2,2) B(3,3) B(1,2) B(1,3) B(2,3) Na .89770 .125 .125 1.58 .00202 .00211 .00186 0 0 .00039 Mg .5 .5 .5 .83 .00104 .00104 .00104 -.00005 -.00005 -.00005 C .28309 .28309 .28309 .80 .00101 .00101 .00101 -.00021 -.00021 -.00021 O .26270 .23011 .35458 1.20 .00186 .00143 .00126 -.0001 .00018 .00032 Cl 0 0 0 2.09 .00264 .00264 .00264 -.00102 .00102 .00102