Fluocerite
Fluocerite is a mineral, a cerium, lanthanum fluoride, formula (Ce,La)F3. It is recognized as two different minerals depending on the cation, fluocerite-(Ce) and fluocerite-(La), corresponding respectively to lanthanum trifluoride and cerium trifluoride. Both crystallize in the trigonal system.
Fluocerite-(Ce) was first described (without the Ce) in 1845 from hydrothermal veins in granite in Sweden. Fluocerite-(La) was first described in 1969 from the type locality in central Kazakhstan.
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