noun
also fers·man·nite ˈfərzməˌnīt, -rsm-
( -s )
Etymology: Russian fersmanit, from Aleksandr E. Fersman died 1945 Russ. mineralogist + Russian -it -ite
: a mineral (Na,Ca) 2 (Ti,Cb)Si(O,F) 6 consisting of a silicate fluoride of sodium, calcium, titanium, and columbium