|
|
Iwakiite Mineral Data
|
|
|
General Iwakiite Information
|
Chemical Formula: |
Mn++(Fe+++,Mn+++)2O4 |
Composition: |
Molecular Weight = 229.99 gm |
|
Manganese 40.61 % Mn 30.84 % MnO / 24.03 % Mn2O3 |
|
Iron 31.57 % Fe 40.61 % FeO |
|
Oxygen 27.83 % O |
|
______ ______ |
|
100.00 % 95.48 % = TOTAL OXIDE |
Empirical Formula: |
Mn2+Fe2+1.3Mn3+0.7O4 |
Environment: |
Regionally metamorphosed bedded manganese deposit. |
IMA Status: |
Approved IMA 1979 |
Locality: |
Gozaisho mine, Iwaki, Fukushima Prefecture, Japan. Link to MinDat.org Location Data. |
Name Origin: |
Named for the locality. |
Name Pronunciation: |
Iwakiite |
Synonym: |
ICSD 76612 |
|
PDF 38-430 |
|
alpha vrendenbergite |
|
vrendenbergite alpha |
|
Iwakiite Image |
Images:
|
|
Iwakiite Crystallography
|
Axial Ratios: |
a:c = 1:1.00246 |
Cell Dimensions: |
a = 8.519, c = 8.54, Z = 8; V = 619.78 Den(Calc)= 4.93 |
Crystal System: |
Tetragonal - Ditetragonal Dipyramidal H-M Symbol (4/m 2/m 2/m) Space Group: P 41/nnm |
X Ray Diffraction: |
By Intensity(I/Io): 2.57(1), 1.506(0.4), 3.016(0.4), |
|
Physical Properties of Iwakiite
|
Cleavage: |
None |
Color: |
Greenish black. |
Density: |
4.85 |
Diaphaneity: |
Opaque |
Habit: |
Aggregates - Made of numerous individual crystals or clusters. |
Habit: |
Anhedral Grains - Granular minerals without the expression of crystal shapes |
Hardness: |
6-6.5 - Orthoclase-Pyrite |
Luster: |
Metallic |
Magnetism: |
Strongly magnetic |
Streak: |
black |
|
Optical Properties of Iwakiite
|
Optical Data: |
Uniaxial (?). |
|
NCalc= 2.03 - from Gladstone-Dale relationship (KC = 0.2094) where Ncalc=Dcalc*KC+1 NCalc= 2.02 - from Gladstone-Dale relationship (KC = 0.2094) where Ncalc=Dmeas*KC+1
|
RL Anisotrophism: |
Moderate, yellowish to brownish gray. |
RL Color: |
Light olive gray. |
Reflectivity |
Standardized Intensity (100%) Reflection Spectra of Iwakiite in Air
λ |
R1 |
R2 |
|
∑ R1(λ) |
∑ R2(λ) |
420 nm |
20.00 |
19.40 |
|
|
|
440 nm |
19.90 |
19.30 |
|
460 nm |
20.30 |
19.50 |
|
480 nm |
20.40 |
19.60 |
|
500 nm |
20.80 |
19.80 |
|
520 nm |
21.20 |
20.10 |
|
540 nm |
21.40 |
20.30 |
|
560 nm |
21.30 |
20.40 |
|
580 nm |
21.20 |
20.10 |
|
600 nm |
21.00 |
20.00 |
|
620 nm |
20.90 |
19.70 |
|
640 nm |
20.50 |
19.60 |
|
660 nm |
20.40 |
19.20 |
|
680 nm |
20.20 |
19.10 |
|
Calculated Relative Intensity Colors of Iwakiite in Air
Relative Intensity |
0% |
50% |
100% |
150% |
200% |
250% |
300% |
350% |
400% |
450% |
R1 |
|
|
|
|
|
|
|
|
|
|
R2 |
|
|
|
|
|
|
|
|
|
|
|
|
Calculated Properties of Iwakiite
|
Electron Density: |
Bulk Density (Electron Density)=4.64 gm/cc note: Specific Gravity of Iwakiite =4.93 gm/cc. |
Fermion Index: |
Fermion Index = 0.006825684 Boson Index = 0.993174316 |
Photoelectric: |
PEIwakiite = 20.39 barns/electron U=PEIwakiite x rElectron Density= 94.68 barns/cc. |
Radioactivity: |
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Iwakiite is Not Radioactive |
|
Iwakiite Classification
|
Dana Class: |
07.02.06.02 (07)Multiple Oxides |
|
(07.02)(A+ B++)2 X4 Spinel group |
|
(07.02.06)Dana Group |
|
07.02.06.01 Kusachiite CuBi2O4 P 4/ncc 4/m 2/m 2/m |
|
07.02.06.02 Iwakiite Mn(Fe,Mn)2O4 P 41/nnm 4/m 2/m 2/m |
Strunz Class: |
04.BB.10 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.10 Hausmannite MnMn2O4 I 41/amd 4/m 2/m 2/m |
|
04.BB.10 Iwakiite Mn(Fe,Mn)2O4 P 41/nnm 4/m 2/m 2/m |
|
04.BB.10 Hydrohetaerolite Zn2Mn4O8•(H2O) I 41/amd 4/m 2/m 2/m |
|
04.BB.10 Hetaerolite ZnMn2O4 I 41/amd 4/m 2/m 2/m |
|
Other Iwakiite Information
|
References: |
NAME( AntBidBlaNic3) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic3) |
See Also: |
Links to other databases for Iwakiite :
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 - MinDAT
10 - Mineralienatlas (Deutsch)
11 - Online Mineral Museum
12 - QUT Mineral Atlas
13 - Ruff.Info
Search for Iwakiite using:
[AOL]
[Bing]
[Dog Pile]
[GeoScienceWorld]
[HotBot]
[Ixquick]
[Lycos]
[MAMMA]
[Scirus]
[Teoma]
[WebCrawler]
[Wikipedia]
[YAHOO]
Visit our Advertisers for Iwakiite :
Ask about Iwakiite here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in
Espa�ol
Print or Cut-and-Paste your Iwakiite Specimen Label here :
Iwakiite
Mn++(Fe+++,Mn+++)2O4
Dana No: 07.02.06.02 Strunz No: 04.BB.10
Locality:
Notes:
|
|
|
|
|
|
Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.