Gaudefroyite Antao S M, Hassan I The Canadian Mineralogist 46 (2008) 183-193 Gaudefroyite, Ca8Mn3+6[(BO3)6(CO3)2O6]: high-temperature crystal structure Locality: Wessels mine, Kalahari manganese field, South Africa Sample: T = 59 C _database_code_amcsd 0006169 10.60643 10.60643 5.88761 90 90 120 P6_3/m atom x y z occ Uiso Ca1 1/3 2/3 .25 .0119 Ca2 .1320 .8317 .25 .0119 B .2166 .7717 .75 .0036 Mn 0 .5 0 .0030 C 0 0 .0601 .5 .0036 O1 .0923 .4738 .25 .0239 O2 .3200 .9195 .75 .0239 O3 .3082 .4755 .5398 .0239 OC .0590 .9155 .5706 .5 .0239