Help mindat.org|Log In|Register|
Home PageMindat NewsThe Mindat ManualHistory of MindatCopyright StatusManagement TeamContact UsAdvertise on Mindat
Donate to MindatSponsor a PageSponsored PagesTop Available PagesMindat AdvertisersAdvertise on MindatThe Mindat Store
Minerals by PropertiesMinerals by ChemistryRandom MineralSearch by minIDLocalities Near MeSearch GlossaryMore Search Options
Search For:
Mineral Name:
Locality Name:
Keyword(s):
 
The Mindat ManualAdd a New PhotoRate PhotosLocality Edit ReportAdd Glossary Item
StatisticsMember ListBooks & MagazinesMineral Shows & EventsThe Mindat DirectoryHow to Link to MindatDevice Settings
Photo SearchPhoto GalleriesNew Photos TodayNew Photos YesterdayMembers' Photo GalleriesPast Photo of the Day Gallery

Maghemite

This page is currently not sponsored. Click here to sponsor this page.
Formula:
Fe23+O3
System:
Isometric
Colour:
Brown, brick-red
Hardness:
6
Name:
From the first syllables of MAGnetite and HEMatite, in allusion to the magnetism and composition.
Dimorph of:
A ferromagnetic iron oxide (which may therefore be confused with magnetite).

Maghemite is formed by weathering or low-temperature oxidation of spinels containing ferrous iron, commonly magnetite or titanian magnetite. It is a widespread yellow pigment in continental sediments, rocks, and soils.

Classification of Maghemite

Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
4.BB.15

4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodates)
B : Metal: Oxygen = 3:4 and similar
B : With only medium-sized cations
4.3.7.1

4 : SIMPLE OXIDES
3 : A2X3
7.20.3

7 : Oxides and Hydroxides
20 : Oxides of Fe
mindat.org URL:
http://www.mindat.org/min-2533.html
Please feel free to link to this page.

Type Occurrence of Maghemite

Year of Discovery:
1927

Physical Properties of Maghemite

Diaphaneity (Transparency):
Opaque
Colour:
Brown, brick-red
Streak:
Brown
Hardness (Mohs):
6

Crystallography of Maghemite

Crystal System:
Isometric
Class (H-M):
4 3 2 - Gyroidal
Space Group:
P41 3 2
Cell Parameters:
a = 8.3515Å
Unit Cell Volume:
V 582.50 ų (Calculated from Unit Cell)
Z:
8
Morphology:
Commonly as coatings on or replacements of magnetite; massive; rarely as minute octahedral crystals, or acicular overgrowths.
Comment:
Cubic (P4132 or P4332), typically with a tetragonal supercell (P41 or P43, a = 8.35, c = 24.99 A).).
X-Ray Powder Diffraction Data:
d-spacingIntensity
2.953 (35)
2.5177 (100)
2.0886 (16)
1.7045 (10)
1.6073 (24)
1.4758 (34)
1.0872 (7)

Optical Data of Maghemite

Type:
Isotropic
Colour in reflected light:
White to greyish blue

Chemical Properties of Maghemite

Formula:
Fe23+O3
Essential elements:
All elements listed in formula:

Relationship of Maghemite to other Species

Series:
Forms a series with Magnetite (see here)
4.BB.05ChromiteFe2+Cr23+O4
4.BB.05Cochromite(Co,Ni,Fe)(Cr,Al)2O4
4.BB.05CoulsoniteFe2+V23+O4
4.BB.05CuprospinelCu2+Fe23+O4
4.BB.05Filipstadite(Sb0.5Fe0.5)Mn2O4
4.BB.05FrankliniteZn2+Fe23+O4
4.BB.05GahniteZnAl2O4
4.BB.05Galaxite(Mn,Fe,Mg)(Al,Fe)2O4
4.BB.05HercyniteFe2+Al2O4
4.BB.05JacobsiteMn2+Fe23+O4
4.BB.05Manganochromite(Mn,Fe)(Cr,V)2O4
4.BB.05MagnesiocoulsoniteMgV2O4
4.BB.05MagnesiochromiteMg(Cr,Al,Fe)2O4
4.BB.05MagnesioferriteMgFe23+O4
4.BB.05MagnetiteFe2+Fe23+O4
4.BB.05Nichromite(Ni,Co,Fe)(Cr,Fe,Al)2O4
4.BB.05Qandilite(Mg,Fe)2(Ti,Fe,Al)O4
4.BB.05SpinelMgAl2O4
4.BB.05TrevoriteNi2+Fe23+O4
4.BB.05UlvöspinelFe2TiO4
4.BB.05Vuorelainenite(Mn,Fe)(V,Cr)2O4
4.BB.05ZincochromiteZnCr2O4
4.BB.10HausmanniteMn2+Mn23+O4
4.BB.10HetaeroliteZnMn2O4
4.BB.10HydrohetaeroliteZnMn2O4 · H2O
4.BB.10IwakiiteMn2+Fe23+O4
4.BB.15TitanomaghemiteFe3+(Fe3+,Ti4+,Fe2+,◻)2O4
4.BB.20Tegengrenite(Mg,Mn2+)2Sb5+0.5(Mn3+,Si,Ti)0.5O4
4.BB.25XieiteFe2+Cr2O4
7.20.1WüstiteFeO
7.20.2MagnetiteFe2+Fe23+O4
7.20.4HematiteFe2O3
7.20.5Goethiteα-Fe3+O(OH)
7.20.6Akaganeiteβ-Fe3+O(OH,Cl)
7.20.7FeroxyhyteFe3+O(OH)
7.20.8Lepidocrociteγ-Fe3+O(OH)
7.20.9FerrihydriteFe103+O14(OH)2
7.20.10Amakinite(Fe2+,Mg)(OH)2
7.20.11MagnesioferriteMgFe23+O4
7.20.12MuskoxiteMg7Fe4O13 · 10H2O
7.20.13SrebrodolskiteCa2Fe23+O5
7.20.14HercyniteFe2+Al2O4
7.20.15BrownmilleriteCa2(Al,Fe3+)2O5

Other Names for Maghemite

Name in Other Languages:
German:Maghemit
Italian:Maghemite
Japanese:磁赤鉄鉱
Simplified Chinese:磁赤铁矿
Spanish:Maghemita

Other Information

Magnetism:
Ferromagnetic
Health Risks:
No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for Maghemite

Reference List:
Sosman and Posnjak (1925) Washington Academy of Science, Journal: 15: 329.

Wagner (1927) Economic Geology: 22: 845.

Schneiderhöhn and Ramdohr (1931) 2: 537.

Winchell (1931) American Mineralogist: 16: 270 (as oxymagnite).

Palache, Charles, Harry Berman & Clifford Frondel (1944) The System of Mineralogy of James Dwight Dana and Edward Salisbury Dana Yale University 1837-1892, Volume I: Elements, Sulfides, Sulfosalts, Oxides. John Wiley and Sons, Inc., New York. 7th edition, revised and enlarged: 708-709.

Contributions to Mineralogy and Petrology (1979) 69: 249.

Internet Links for Maghemite

Localities for Maghemite

map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
Mineral and/or Locality  
Mindat.org is an outreach project of the Hudson Institute of Mineralogy, a 501(c)(3) not-for-profit organization.
Copyright © mindat.org and the Hudson Institute of Mineralogy 1993-2015, except where stated. Mindat.org relies on the contributions of thousands of members and supporters.
Privacy Policy - Terms & Conditions - Contact Us Current server date and time: August 30, 2015 04:37:07 Page generated: August 27, 2015 13:10:45