Phenakite Hazen R M, Finger L W Physics and Chemistry of Minerals 14 (1987) 426-434 High-temperature crystal chemistry of phenakite (Be2SiO4) and Chrysoberyl (BeAl2O4) Sample: T = 270 C _database_code_amcsd 0007440 12.449 12.449 8.240 90 90 120 R-3 atom x y z Biso Be1 .19384 .20985 .41545 .64 Be2 .19430 .21157 .08379 .67 Si .19557 .21152 .74995 .37 O1 .20965 .08856 .75032 .59 O2 .33348 .33323 .75008 .53 O3 .12234 .20978 .91468 .60 O4 .12233 .20884 .58555 .57