Constituent Glauconite | SSHADE

Constituent

Name: Glauconite
IMA name: Glauconite

Class: silicate mineral
Compound type: phyllosilicate

Constituent abundance in material

Relevance: main - major
Arrangement: single phase
Mass fraction: 1.0

Chemical composition

Formula: $(K,Na)(Fe^{3+},Al,Mg)_2(Si,Al)_4O_{10}(OH)_2$
Chemical formula: (K,Na)(Fe3+,Al,Mg)2(Si,Al)4O10(OH)2
Elemental formula: (K)0-1 (Na)0-1 (Mg)0-2 (Al)0-2 (Fe3+)0-2 (Si)3-4 O10 H2 (O-)2
Isotope mixture type: terrestrial abundance

	Formula	Name	Family	Number min-max	Isotope mole fraction	State	Relevance
	$K$	Potassium	element	0 - 1		constituent element	main
	$Na$	Sodium	element	0 - 1		constituent element	main
	$Mg$	Magnesium	element	0 - 2		constituent element	main
	$Al$	Aluminium	element	0 - 2		constituent element	main
	$Fe^{3+}$	Iron(III) cation	element	0 - 2		constituent element	main
	$Si$	Silicon	element	3 - 4		constituent element	main
	$O$	Oxygen	element	10		constituent element	main
	$(OH)^-$	Hydroxide anion	chemical function	2		anionic radical	main

Composition comments: Common Impurities: Fe^{2+}, Ti, Ca, P

Chemical functions and bonds

Chemical functions

	Function	Number
	$(OH)^-$	2
	$((Si_2O_5)^{2-})_n$	2

Chemical bonds

	Bond	Number
	$O^--H$	1
	$\geq Si-O-$	6
	$\geq Si-O^-$	2

Oxides composition

Oxides

Formula	$K_{2}O$	$Na_{2}O$	$MgO$	$Al_{2}O_{3}$	$FeO$	$Fe_{2}O_{3}$	$SiO_{2}$	$H_{2}O$
Mass fraction (%)	6.62	0.36	3.78	3.58	24.31	3.37	53.48	4.22

Classifications

Strunz

Class: silicates (09)
Division: phyllosilicate (09.E)
Family: with mica sheets, composed of tetrahedral and octahedral nets (09.EC)
Code: 09.EC.15

Dana

Major class: silicates (VIII)
Class: phyllosilicate sheets of six-membered rings (71)
Type: with 2:1 layers (71.02)
Group: Mica group (Muscovite subgroup) (71.02.02a)
Code: 71.02.02a.05

Phase type: crystalline

Crystallography

Crystal system: monoclinic
Crystal class: prismatic
Crystal class symbol: 2/m (C2h)
Crystal spacegroup: C2/m

Physical properties

Molar mass: 426.93 $g/mol$
Density: 2.4 - 2.95 $g/cm^3$

Optical properties

Refringence type: biaxial
Refringence sign: negative
Birefringence: 0.0200 - 0.0320
Refraction index $n_{\alpha}$: 1.59 - 1.612
Refraction index $n_{\beta}$: 1.609 - 1.643
Refraction index $n_{\gamma}$: 1.61 - 1.644
Dispersion V: r > v
Diaphaneity: translucent to opaque
Luster: earthy