Maghemite Mineral Data (original) (raw)

General Maghemite Information

Help on Chemical Formula: Chemical Formula:

gamma-Fe+++2O3

Help on Composition: Composition:

Molecular Weight = 159.69 gm

Iron 69.94 % Fe 100.00 % Fe2O3

Oxygen 30.06 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Help on Empirical Formula: Empirical Formula:

Fe3+2O3

Help on Environment: Environment:

Formed by weathering or low-temperature oxidation of spinels containing ferrous iron, commonly magnetite or titanian magnetite. Widespread yellow pigment in sediments.

Help on IMA Status: IMA Status:

Valid Species (Pre-IMA) 1927

Help on Locality: Locality:

Iron mountain mine, 9.5 miles NW of Redding, Shasta Co., California. Link to MinDat.org Location Data.

Help on Name Origin: Name Origin:

From MAGnetite and HEMatite, in allusion to the mineral's magnetism and composition.

Help on Name Pronunciation: Name Pronunciation:

Maghemite + Pronunciation Say MAGHEMITE

Maghemite Image

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Maghemite Crystallography

Help on Cell Dimensions: Cell Dimensions:

a = 8.339, Z = 12; V = 579.89 Den(Calc)= 5.49

Help on Crystal System: Crystal System:

Isometric - TetartoidalH-M Symbol (2 3) Space Group: P 213

Help on X Ray Diffraction: X Ray Diffraction:

By Intensity(I/Io): 1.61(1), 2.52(1), 2.95(1),

Click Here for Large Maghemite Structure Window Crystal Structure:

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Help on Above

| | Pecharroman C , Gonzalez-Carreno T , Iglesias J E , Physics and Chemistry of Minerals , 22 (1995) p.21-29, The infrared dielectric properties of maghemite, gamma-Fe2O3,, from reflectance measurement on pressed powders, Sample: c) idealized, either one of Fe-oct 1-6,, or both Fe-oct 6-7 have zero occupancy View Additional jPOWD Structure files for Maghemite [2] | | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |

Physical Properties of Maghemite

Help on Cleavage: Cleavage:

None

Help on Color: Color:

Dark brown.

Help on Density: Density:

4.9

Help on Diaphaneity: Diaphaneity:

Opaque

Help on Fracture: Fracture:

Sub Conchoidal - Fractures developed in brittle materials characterized by semi-curving surfaces.

Help on Habit: Habit:

Massive - Granular - Common texture observed in granite and other igneous rock.

Help on Habit: Habit:

Massive - Uniformly indistinguishable crystals forming large masses.

Help on Hardness: Hardness:

6 - Orthoclase

Help on Luster: Luster:

Metallic

Help on Magnetism: Magnetism:

Strongly magnetic

Help on Streak: Streak:

brown

Optical Properties of Maghemite

Help on Optical Data: Optical Data:

Isotropic.

NCalc= 2.73 - from Gladstone-Dale relationship (KC = 0.315) where Ncalc=Dcalc*KC+1
NCalc= 2.54 - from Gladstone-Dale relationship (KC = 0.315) where Ncalc=Dmeas*KC+1

Help on RL Color: RL Color:

White to bluish gray.

Help on Reflectivity Reflectivity

Standardized Intensity (100%) Reflection Spectra of Maghemite in Air

λ R ∑ R(λ)
400 nm 31.50
420 nm 30.20
440 nm 28.50
460 nm 27.60
480 nm 26.60
500 nm 26.00
520 nm 25.50
540 nm 24.80
560 nm 24.00
580 nm 23.20
600 nm 22.40
620 nm 22.00
640 nm 21.60
660 nm 21.20
680 nm 20.80
700 nm 20.40

Calculated Relative Intensity Colors of Maghemite in Air

RelativeIntensity 0% 40% 80% 100% 120% 160% 200% 240% 280% 320% 360% 390%
R

Calculated Properties of Maghemite

Help on Electron Density: Electron Density:

Bulk Density (Electron Density)=5.23 gm/cc
note: Specific Gravity of Maghemite =5.49 gm/cc.

Help on Fermion Index: Fermion Index:

Fermion Index = 0.01
Boson Index = 0.99

Help on Photoelectric: Photoelectric:

PEMaghemite = 21.37 barns/electron
U=PEMaghemite x rElectron Density= 111.70 barns/cc.

Help on Radioactivity: Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Maghemite is Not Radioactive

Maghemite Classification

Help on Dana Class: Dana Class:

04.03.07.01 (04)Simple Oxides

(04.03)with a cation charge of 3+ (A+++2 O3)

(04.03.07)Dana Group

04.03.07.01 Maghemite gamma-Fe2O3 P 213 2 3

04.03.07.02 Bixbyite (Mn,Fe)2O3 I a3 2/m 3

Help on Strunz Class: Strunz Class:

04.BB.15 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.B - Metal:Oxygen = 3:4 and similar

04.BB -With only medium-sized cations

04.BB.15 Maghemite gamma-Fe2O3 P 213 2 3

Other Maghemite Information

Help on References: References:

NAME( MinRec) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic3)

Help on See Also: See Also:

Links to other databases for Maghemite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info

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Ask about Maghemite here :
Ask-A-Mineralogist from the Mineralogical Society of America
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Print or Cut-and-Paste your Maghemite Specimen Label here :

Maghemite

gamma-Fe+++2O3
Dana No: 04.03.07.01 Strunz No: 04.BB.15
Locality:

Notes: