Class

silicate mineral

Compound type

inosilicate

Chemical functions

	Function	Number
	$(SiO_4)^{4-}$	1

Chemical bonds

	Bond	Number
	$\geq Si-O^-$	4

Oxides

Formula	$Na_{2}O$	$ZrO_{2}$	$SiO_{2}$
Mass fraction (%)	14.56	28.96	56.48

Strunz

Class

silicates (09)

Division

inosilicate (09.D)

Family

with 6-periodic single chains (09.DM)

Code

09.DM.25

Dana

Major class

silicates (VIII)

Class

inosilicate double-width unbranched chains, w=2 (66)

Type

with P=2 non-amphibole configuration (66.02)

Group

Dana group (Vlasovite) (66.02.02)

Code

66.02.02.01

Phase type

crystalline

Crystal system

monoclinic

Crystal class

prismatic

Crystal class symbol

2/m (C2h)

Crystal spacegroup

C2/c

Texture

polycrystalline

Molar mass

425.54 $g/mol$

Density

2.97 $g/cm^3$

Refringence type

biaxial

Refringence sign

negative

Birefringence

0.0210

Refraction index $n_{\alpha}$

1.607

Refraction index $n_{\beta}$

1.623

Refraction index $n_{\gamma}$

1.628

Diaphaneity

transparent

Luster

greasy