Iddingsite | SSHADE

Processing math: 100%

Mineral phase

IMA name: Iddingsite

Class: silicate mineral
Compound type: silicate

Chemical composition

Formula: $MgOFe_2O_3 3SiO_2 \bullet 4(H_2O)$
Chemical formula: MgO Fe2O3 3SiO2 •n(H2O)
Elemental formula: Mg (Fe2+)2 Si3 O10
Isotope mixture type: terrestrial abundance

	Formula	Name	Family	Number min-max	Isotope mole fraction	State	Relevance
	$Mg$	Magnesium	element	1		constituent element	main
	$Fe^{2+}$	Iron(II) cation	element	2		constituent element	main
	$Si$	Silicon	element	3		constituent element	main
	$O$	Oxygen	element	10		constituent element	main

Oxides composition

Oxides

Formula	$MgO$	$FeO$	$SiO_{2}$	$H_{2}O$
Mass fraction (%)	8.91	31.77	39.85	15.93

Classifications

Strunz

Class: silicates (09)
Division: unclassified silicates (09.H)
Family: Unclassified Silicate (09.HX)
Code: 09.HX.00

Dana

Major class: silicates (VIII)
Class: unclassified silicates (78)
Type: Without Dana Classification Numbers (78.00)
Group: Unclassified Silicate (78.00.00)
Code: 78.00.00.00

Crystallography

Phase type: crystalline
Crystal system: orthorhombic
Crystal class: unknown
Crystal class symbol: unknown
Crystal spacegroup: unknown

Physical properties

Molar mass: 452.31 $g/mol$
Density: 2.5-2.8 $g/cm^3$

Thermodynamical properties

State NTP: solid

Optical properties

Refringence type: biaxial
Refringence sign: negative
Birefringence: 0.040 - 0.050
Refraction index $n_{\alpha}$: 1.67 - 1.73
Refraction index $n_{\beta}$: 1.7 - 1.76
Refraction index $n_{\gamma}$: 1.72 - 1.77
Dispersion V: relatively strong
Pure color: brown
Color: brown
Diaphaneity: transparent to translucent
Luster: vitreous

Links and Publications

Links