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
	$(PO_4)^{3-}$	2
	$R-OH$	2

Chemical bonds

	Bond	Number
	$-O-H$	2
	$\dddot - \dddot - \dddot - P \dddot - O^{-3/4}$	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

Refringence type

uniaxial

Refringence sign

positive

Birefringence

0.005

Refraction index $n_o$ (w)

1.618

Refraction index $n_e$ (e)

1.623

Pure color

white

Color

gray, yellow, yellowish white, light red

Diaphaneity

transparent to subtranslucent

Luster

vitreous

Links

• Wikipedia
• Webmineral
• Mindat