Cerite is a complex silicate mineral group containing cerium, formula (Ce,La,Ca)
9(Mg,Fe3+
)(SiO
4)
6(SiO
3OH)(OH)
3. The cerium and lanthanum content varies with the Ce rich species (cerite-(Ce)) and the La rich species (cerite-(La)). Analysis of a sample from the Mountain Pass carbonatite gave 35.05% Ce
2O
3 and 30.04% La
2O
3.
Cerite was first described in 1803 for an occurrence in Bastnäs in Västmanland, Sweden. The lanthanum rich species, cerite-(La) was first described for an occurrence in the Khibina massif, Kola Peninsula, Russia in 2002.
