Constituent Crandallite | SSHADE

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 and bonds

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 composition

Oxides

Formula	$CaO$	$Al_{2}O_{3}$	$P_{2}O_{5}$	$H_{2}O$
Mass fraction (%)	13.54	36.94	34.28	15.23

Classifications

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

Crystallography

Crystal system: trigonal
Crystal class: ditrigonal-scalenohedral
Crystal class symbol: -3m (D3d)
Crystal spacegroup: R-3m

Texture: monocrystalline

Physical properties

Molar mass: 414.02 $g/mol$
Density: 2.78-2.92 $g/cm^3$

Optical properties

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