IMA Code

Sdl

	Formula	Name	Family	Number min-max	Isotope mole fraction	State	Relevance
	$Na^+$	Sodium cation	element	8		constituent cation	main
	$Al$	Aluminium	element	6		constituent element	main
	$Si$	Silicon	element	6		constituent element	main
	$O$	Oxygen	element	24		constituent element	main
	$Cl^-$	Chloride anion	element	2		constituent anion	main

Composition comments

all O atoms carries a charge of -1/4

Chemical bonds

	Bond	Number
	$>Al-O-$	24
	$\geq Si-O-$	24
	$Na^+ \cdot O^{-}-$	6
	$Na^+ \cdot Cl^-$	2

Oxides

Formula	$Na_{2}O$	$Al_{2}O_{3}$	$SiO_{2}$	$Cl$
Mass fraction (%)	25.58	31.56	37.2	7.32

Oxides comments

-1.65 % -O=Cl2

Strunz

Class

silicates (09)

Division

tektosilicate without zeolitic H2O (09.F)

Family

with additional anions (09.FB)

Code

09.FB.10

Dana

Major class

silicates (VIII)

Class

tectosilicate Al-Si framework (76)

Type

Feldspathoids and related species (76.02)

Group

Sodalite group (76.02.03)

Code

76.02.03.01

Phase type

crystalline

Crystal system

isometric (cubic)

Crystal class

hextetrahedral

Crystal class symbol

-43m (Td)

Crystal spacegroup

P-43n

Refringence type

isotropic

Refringence sign

no

Birefringence

0

Refraction index $n_{\alpha}$

1.483 - 1.484

Pure color

colorless

Color

azure blue, white, pink, gray, green

Diaphaneity

transparent to translucent

Luster

vitreous

Links

• MinDAT: Sodalite
• WebMineral: Sodalite
• Wikipedia: Sodalite