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 = 690 C _database_code_amcsd 0007442 12.482 12.482 8.266 90 90 120 R-3 atom x y z Biso Be1 .19381 .21010 .41550 1.05 Be2 .19426 .21133 .08448 1.12 Si .19554 .21162 .74998 .63 O1 .20982 .08888 .75048 .97 O2 .33312 .33288 .75013 .93 O3 .12248 .20976 .91413 .98 O4 .12219 .20875 .58607 1.00