Mineral phase
IMA name
Fluocerite-(La)
IMA Code
Fcrt-La
Type
Class
non-silicate mineral
Compound type
fluoride
Chemical composition
Formula
$(La,Ce)F_3$
Chemical formula
(La,Ce)F3
Elemental formula
(La3+)0.5-1 (Ce3+)0-0.5 (F-)3
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$La^{3+}$ Lanthanum cation element 0.5 - 1 constituent cation main
$Ce^{3+}$ Cerium cation element 0 - 0.5 constituent cation main
$F^-$ Fluoride anion element 3 constituent anion main
Composition comments
typical formula: $La_{0.9}Ce_{0.1}F_3$
Chemical bonds
  Bond Number
$\cdot (\cdot) La^{3+} \cdot F^{-}$ 3
Oxides
Formula $La_{2}O_{3}$ $Ce_{2}O_{3}$ $F$
Mass fraction (%) 74.79 8.37 29.08
Oxides comments
-12.24 % -O=F2, for $La_{0.9}Ce_{0.1}F_3$

Strunz

Class
halides (03)
Division
simple halides, without H2O (03.A)
Family
M:X = 1:3 (03.AC)
Code
03.AC.15

Dana

Major class
halides (IV)
Class
anhydrous and hydrated halides (09)
Type
-others- (09.03)
Group
Fluocerite Group (09.03.04)
Code
09.03.04.02
Phase type
crystalline
Crystal system
trigonal
Crystal class
ditrigonal-scalenohedral
Crystal class symbol
-3m (D3d)
Crystal spacegroup
P-3c1
Molar mass
196.02 $g/mol$
Density
5.93 $g/cm^3$
State NTP
solid
Refringence type
uniaxial
Refringence sign
negative
Birefringence
0.0060
Refraction index $n_o$ (w)
1.609
Refraction index $n_e$ (e)
1.603
Pure color
yellow
Color
greenish yellow
Diaphaneity
transparent to translucent
Luster
vitreous
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