Constituent
Name
Crandallite
IMA name
Crandallite
Class
non-silicate mineral
Compound type
phosphate
Constituent abundance in material
Relevance
main - major
Arrangement
single phase
Mass fraction
1.0 $\pm$ 0.01
Chemical composition
Formula
$CaAl_3(PO_4)_2(OH)_5 \bullet (H_2O)$
Chemical formula
CaAl3(PO4)2(OH)5•(H2O)
Elemental formula
Ca Al3 P2 O14 H7
Isotope mixture type
terrestrial abundance
  Formula Name Family Number min-max Isotope mole fraction State Relevance
$Ca$ Calcium element 1 constituent element main
$Al$ Aluminium element 3 constituent element main
$(PO_4)^{3-}$ Phosphate anion chemical function 2 anionic radical main
$(OH)^-$ Hydroxide anion chemical function 5 anionic radical main
$H_2O$ Water molecule 1 hydration main
Chemical functions
  Function Number Relevance
$(PO_4)^{3-}$ 2
$R-OH$ 2 main
Chemical bonds
  Bond Number Relevance
$-O-H$ 2 main
$\dddot - \dddot - \dddot - P \dddot - O^{-3/4}$ 4
Oxides
Formula $CaO$ $Al_{2}O_{3}$ $P_{2}O_{5}$ $H_{2}O$
Mass fraction (%) 13.54 36.94 34.28 15.23

Strunz

Class
phosphates - arsenates - vanadates (08)
Division
phosphates, etc. with additional anions, without H2O (08.B)
Family
with medium-sized and large cations, (OH, etc.):RO4 = 3:1 (08.BL)
Code
08.BL.10

Dana

Major class
phosphates, arsenates, vanadates (VII)
Class
hydrated phosphates containing hydroxyl or halogen (42)
Type
where (AB)2 (XO4) Zq·x(H2O) (42.07)
Group
Crandallite group (42.07.03)
Code
42.07.03.01
Phase type
crystalline
Crystal system
trigonal
Crystal class
ditrigonal-scalenohedral
Crystal class symbol
-3m (D3d)
Crystal spacegroup
R-3m
Texture
monocrystalline
Molar mass
414.02 $g/mol$
Density
2.78-2.92 $g/cm^3$
Refringence type
uniaxial
Refringence sign
positive
Birefringence
0.005
Refraction index $n_{\alpha}$
1.618
Refraction index $n_{\beta}$
1.623
Color
gray, yellow, yellowish white, light red
Diaphaneity
transparent to subtranslucent
Luster
vitreous