H5O15Si4Sr3Ti
Mizota, T.Komatsu, M.Chihara, K.
Mineralogical Journal (1973) 7, 302-305
a=10.958Å b=7.778Å c=7.799Å
α=90° β=100.90° γ=90°
H6O15.274Si4Sr3Ti
American Mineralogist (1983) 68, 811-817
a=10.979Å b=7.799Å c=7.818Å
α=90° β=100.9° γ=90°