author(s) : Sahama and Hytoenen
date of publication : 1957
source : Min.Mag.(31) p.503-510
formula : (Ca,Na)7 (Ti,Al)2 Si4O15(F,OH)3
comments about the origin : Sahama 1967
This type specimen, kept in the Museum of Ecole des mines de Paris, has been indexed by Dr Guillemin.
(C) BRGM, ENSMP