Spinel Princivalle F, Martignago F, Dal Negro A American Mineralogist 91 (2006) 313-318 Kinetics of cation ordering in natural Mg(Al,Cr3+)2O4 spinels Locality: Olkhon metamorphic complex, Lake Baikal, Russia Sample: Ch, annealed at T = 650 C, ordering, t = 36 m _database_code_amcsd 0004070 8.0863 8.0863 8.0863 90 90 90 *Fd3m .125 .125 .125 atom x y z occ MgT .125 .125 .125 .743 AlT .125 .125 .125 .257 AlM .5 .5 .5 .728 MgM .5 .5 .5 .257 Cr3+M .5 .5 .5 .015 O .26182 .26182 .26182