Aragonite Antao S M, Hassan I The Canadian Mineralogist 47 (2009) 1245-1255 The orthorhombic structure of CaCO3, SrCO3, PbCO3 and BaCO3: Linear structural trends Locality: Italy Note: HRPXRD _database_code_amcsd 0006301 4.96062 7.97006 5.74181 90 90 90 Pmcn atom x y z Uiso Ca .25 .41502 .7577 .0066 C .25 .7616 -.0808 .0115 O1 .25 .9220 -.0944 .0115 O2 .4750 .6824 -.0905 .0115