Akimotoite Mineral Data

General Akimotoite Information

Chemical Formula:

(Mg,Fe)SiO3

Composition:

Molecular Weight = 108.27 gm

Magnesium 16.84 % Mg 27.92 % MgO

Iron 12.89 % Fe 16.59 % FeO

Silicon 25.94 % Si 55.49 % SiO₂

Oxygen 44.33 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mg_0.75Fe²⁺_0.25SiO₃

Environment:

Found in fragments within veins of shock-induced melt. A member of the Ilmenite group. Dimorphic relationship with enstatite and clinoenstatite.

IMA Status:

Approved IMA 1998 (Dana # Added)

Locality:

Tenham chondritic meteorite, which fell in 1879 in South Gregory, Queensland, Australia. Link to MinDat.org Location Data.

Name Origin:

Named after Syun-iti Akimoto (b. 1925), of the Institute of Geophysics and Solid State Physics, University of Tokyo, specialist in high-pressure research, especially on phase relati onships in the system (Mg,Fe)2 SiO4 at

Name Pronunciation:

Akimotoite + Pronunciation

Synonym:

IMA1997-044

Akimotoite Image

Images:

Akimotoite

Comments: Electron micrograph of akimotoite (Ak) as columnar grains. Aggregates of akimotoite are adjacent to a large clinoenstatite grain (Cen) with (100) twin lamallae. (AmMin 84:268).
Location: Shock-metamorphosed Tenham chondrite. Scale: See Image.
© American Mineralogist

Akimotoite Crystallography

Axial Ratios:

a:c = 1:2.84518

Cell Dimensions:

a = 4.78, c = 13.6, Z = 4; V = 269.11 Den(Calc)= 2.67

Crystal System:

Trigonal - Rhombohedral H-M Symbol ( 3) Space Group: R 3

$Help on X Ray Diffraction:$ X Ray Diffraction:

By Intensity(I/I_o): 2.616(1), 1.636(0.65), 3.509(0.61),

Physical Properties of Akimotoite

Color:

Colorless.

Diaphaneity:

Transparent

Luster:

Vitreous (Glassy)

Optical Properties of Akimotoite

Optical Data:

NCalc= 1.54 - from Gladstone-Dale relationship (KC = 0.2024) where Ncalc=Dcalc*KC+1

Calculated Properties of Akimotoite

Electron Density:

Bulk Density (Electron Density)=2.64 gm/cc
note: Specific Gravity of Akimotoite =2.67 gm/cc.

Fermion Index:

Fermion Index = 0.03
Boson Index = 0.97

Photoelectric:

PE_Akimotoite= 5.17 barns/electron
U=PE_Akimotoite x rElectron Density= 13.64 barns/cc.

Radioactivity:

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

Akimotoite Classification

Dana Class:

04.03.05.07 (04)Simple Oxides

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

(04.03.05)Ilmenite Group

04.03.05.01 Ilmenite FeTiO3 R 3 3

04.03.05.02 Geikielite MgTiO3 R 3 3

04.03.05.03 Pyrophanite MnTiO3 R 3 3

04.03.05.04 Ecandrewsite (Zn,Fe,Mn)TiO3 R 3 3

04.03.05.05 Melanostibite Mn(Sb,Fe)O3 R 3 3

04.03.05.06 Brizziite-III NaSbO3 R 3 3

04.03.05.07 Akimotoite! (Mg,Fe)SiO3 R 3 3

Strunz Class:

09.DA.05 09 - SILICATES (Germanates)

09.D - Inosilicates* Structural terminology according to Liebau (1985)

09.DA -Inosilicates with 2-periodic single chains, Si2O6; pyroxene family

09.DA.05 Donpeacorite (Mn,Mg)MgSi2O6 P bca 2/m 2/m 2/m

09.DA.05 Akimotoite! (Mg,Fe)SiO3 R 3 3

09.DA.05 Enstatite Mg2Si2O6 P bca 2/m 2/m 2/m

09.DA.05 Ferrosilite (Fe,Mg)2Si2O6 P bca 2/m 2/m 2/m

Other Akimotoite Information

References:

NAME( AmMin, Vol 84) PHYS. PROP.(Eur. J. Min.,Vol.10,1998)

See Also:

Links to other databases for Akimotoite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info

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Print or Cut-and-Paste your Akimotoite Specimen Label here :

Akimotoite

(Mg,Fe)SiO3
Dana No: 04.03.05.07 Strunz No: 09.DA.05
Locality:

Notes:

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