Amesite subgroup | SSHADE

Mineral phase

IMA name: Amesite subgroup

Class: silicate mineral
Compound type: phyllosilicate

Chemical composition

Formula: $(Fe^{2+},Fe^{3+},Mn^{2+},Mg,Ni,Al,Zn,Li)_{2-3}(Si,Al,Fe^{3+},B)_2O_5(OH)_4$
Chemical formula: (Fe2+,Fe3+,Mn2+,Mg,Ni,Al,Zn,Li)2-3(Si,Al,Fe3+,B)2O5(OH)4
Elemental formula: (Fe2+)0-2 (Fe3+)0-2 (Mn2+)0-2 (Mg)0-2 (Al)0-3 (Zn)0-3 (Li)0-2 (Ni)0-2 (B)0-0.5 (Si)1-2 O9 H4
Isotope mixture type: terrestrial abundance

	Formula	Name	Family	Number min-max	Isotope mole fraction	State	Relevance
	$Fe^{2+}$	Iron(II) cation	element	0 - 2		constituent element	main
	$Fe^{3+}$	Iron(III) cation	element	0 - 2		constituent element	main
	$Mn^{2+}$	Manganese(II) cation	element	0 - 2		constituent element	main
	$Mg$	Magnesium	element	0 - 2		constituent element	main
	$Al$	Aluminium	element	0 - 3		constituent element	main
	$Zn$	Zinc	element	0 - 3		constituent element	main
	$Li$	Lithium	element	0 - 2		constituent element	main
	$Ni$	Nickel	element	0 - 2		constituent element	main
	$B$	Boron	element	0 - 0.5		constituent element	main
	$Si$	Silicon	element	1 - 2		constituent element	main
	$O$	Oxygen	element	9		constituent element	main
	$H$	Hydrogen	element	4		constituent element	main

Composition comments: Common impurities: Ti, Ca

Chemical functions and bonds

Chemical functions

	Function	Number
	$(OH)^-$	4

Chemical bonds

	Bond	Number
	$O^--H$	1

Oxides composition

Oxides

Formula	$FeO$	$Fe_{2}O_{3}$	$MnO$	$MgO$	$NiO$	$ZnO$	$Li_{2}O$	$B_{2}O_{3}$	$Al_{2}O_{3}$	$SiO_{2}$	$H_{2}O$
Mass fraction (%)

Classifications

Strunz

Class: silicates (09)
Division: phyllosilicate (09.E)
Family: with kaolinite layers composed of tetrahedral and octahedral nets (09.ED)
Code: 09.ED.15

Dana

Major class: silicates (VIII)
Class: phyllosilicate sheets of six-membered rings (71)
Type: with 1:1 layers (71.01)
Group: Serpentine group (Amesite subgroup) (71.01.02c)

Endmembers and polymorphs

End-members

Crystallography

Phase type: crystalline
Crystal system: various
Crystal class: various
Crystal class symbol: various
Crystal spacegroup: various

Physical properties

Molar mass: 278.68 - 399.5 $g/mol$
Density: 2.77 - 3.54 $g/cm^3$

Thermodynamical properties

State NTP: solid

Optical properties

Refringence type: various
Refringence sign: positive or negative
Pure color: various
Color: white, brown green, light green, dark green, green yellow, reddish brown, greenish brown, black, yellowish white, lemon yellow, colorless
Diaphaneity: various

Links and Publications

Links

Webmineral database