Arakiite Mineral Data

General Arakiite Information

Chemical Formula:

(Zn,Mn++)(Mn++,Mg)12(Fe+++,Al)2(AsO3)(AsO4)2(OH)23

Composition:

Molecular Weight = 1,452.97 gm

Magnesium 7.86 % Mg 13.04 % MgO

Manganese 27.60 % Mn 35.64 % MnO

Aluminum 1.30 % Al 2.46 % Al₂O₃

Zinc 3.74 % Zn 4.65 % ZnO

Iron 5.00 % Fe 7.14 % Fe₂O₃

Arsenic 15.47 % As 6.81 % As₂O₃ / 15.82 % As₂O₅

Hydrogen 1.60 % H 14.26 % H₂O

Oxygen 37.44 % O

______ ______

100.00 % 99.81 % = TOTAL OXIDE

Empirical Formula:

Zn_0.83Mn²⁺_7.3Mg_4.7Fe³⁺_1.3Al_0.7(AsO₃)(AsO₄)₂(OH)₂₃

Environment:

Megascopically indistinguishable from hematolite or dixenite.

IMA Status:

Approved IMA 1999 (Dana # Added)

Locality:

Found on a museum specimen, previously identified as dixenite from Langban, Varmland, Sweden. Link to MinDat.org Location Data.

Name Origin:

Named for Dr. Takaharu Araki (1929-), University of Chicago, for his numerous crystal-structure contributions to the science of mineralogy.

Synonym:

ICSD 87742

IMA1998-062

PDF 89-821

Arakiite Image

Images:

Arakiite

Comments: Deep red massive arakiite between grains.
Location: Nordmark, Sweden. Scale: See Image.
© Rruff Database

Arakiite Crystallography

Axial Ratios:

a:b:c =1.7316:1:2.9448

Cell Dimensions:

a = 14.248, b = 8.228, c = 24.23, Z = 4; beta = 93.62° V = 2,834.88 Den(Calc)= 3.40

Crystal System:

Monoclinic - DomaticH-M Symbol (m) Space Group: Cc

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

By Intensity(I/I_o): 12.07(1), 6.046(1), 4.04(0.9),1.552(0.7), 3.03(0.7), 2.411(0.4), 3.148(0.3),

Crystal Structure:

Mouse
drag1 - LMB Manipulate Structure
drag2 - RMB Resize/Rotate
Keyboard
S - Stereo Pair on/off
H - Help Screen
I - Data Info
A - Atoms On/Off
P - Polyhedra On/Off
B - Bonds On/Off
Help on Above

Cooper M A , Hawthorne F C , The Canadian Mineralogist , 37 (1999) p.1471-1482, The effect of differences in coordination on ordering of, polyvalent cations in close-packed structures: The crystal, structure of arakiite and comparison with hematolite

Physical Properties of Arakiite

Cleavage:

{001} Perfect

Color:

Reddish brown, Orange brown.

Diaphaneity:

Opaque to translucent

Fracture:

Brittle - Uneven - Very brittle fracture producing uneven fragments.

Habit:

Aggregates - Made of numerous individual crystals or clusters.

Habit:

Anhedral Grains - Granular minerals without the expression of crystal shapes

Habit:

Micaceous - Platy texture with "flexible" plates.

Hardness:

3-4 - Calcite-Fluorite

Luster:

Resinous - Metallic

Streak:

pale brown

Optical Properties of Arakiite

Gladstone-Dale:

CI calc= 0.018 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2174,KC= 0.2213
Ncalc = 1.75

Optical Data:

Biaxial (-), a=1.723, b=1.744, g=1.75, bire=0.0270, 2V(Calc)=54, 2V(Meas)=40-44. Dispersion r > v medium.

Calculated Properties of Arakiite

Electron Density:

Bulk Density (Electron Density)=3.28 gm/cc
note: Specific Gravity of Arakiite =3.40 gm/cc.

Fermion Index:

Fermion Index = 0.01
Boson Index = 0.99

Photoelectric:

PE_Arakiite= 21.07 barns/electron
U=PE_Arakiite x rElectron Density= 69.08 barns/cc.

Radioactivity:

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

Arakiite Classification

Dana Class:

46.02.08.02 (46)Basic or Halogen-Containing Antimonites, Arsenites and Phosphites

(46.02)with miscellaneous formulae

(46.02.08)Dixenite Group

46.02.08.01 Dixenite CuMn14Fe(AsO3)5(SiO4)2(AsO4)(OH)6 R 3 3

46.02.08.02 Arakiite! (Zn,Mn)(Mn,Mg)12(Fe,Al)2(AsO3)(AsO4)2(OH)23 Cc m

Strunz Class:

08.BE.45 08 - PHOSPHATES, ARSENATES, VANADATES

08.B - Phosphates, etc. with Additional Anions, without H2O

08.BE -With only medium-sized cations, (OH, etc.):RO4 > 2:1

08.BE.45 Dixenite CuMn14Fe(AsO3)5(SiO4)2(AsO4)(OH)6 R 3 3

08.BE.45 Hematolite (Mn,Mg,Al)15(AsO3)(AsO4)2(OH)23 R 3 3

08.BE.45 Kraisslite (Mn,Mg)24Zn3Fe(AsO3)2(AsO4)3(SiO4)6(OH)18 P 6₃22 6 2 2

08.BE.45 Mcgovernite Mn9Mg4Zn2As2Si2O17(OH)14 R 3c 3 2/m

08.BE.45 Turtmannite! (Mn,Mg)25.5[(V,As)O4]3(SiO4)3[AsO3]xO5-5x(OH)20x R 3c 3 2/m

08.BE.45 Arakiite! (Zn,Mn)(Mn,Mg)12(Fe,Al)2(AsO3)(AsO4)2(OH)23 Cc m

Other Arakiite Information

References:

NAME( MinRec, V31, p253) PHYS. PROP.(MinRec, V31, p253) OPTIC PROP.(MinRec, V31, p253)

See Also:

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

Search for Arakiite using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Arakiite :

A Bijoux Google Search for Arakiite
Adam's Minerals Google Search for Arakiite
Cape Minerals Google Search for Arakiite
Dakota Matrix Minerals Google Search for Arakiite
Excalibur Mineral Corp. Google Search for Arakiite
Exceptional Minerals Google Search for Arakiite
John Betts Fine Minerals Search for Arakiite
McDougall Minerals Google Search for Arakiite
Mineral News Website Link
Rock and Mineral Shows Google Search for Arakiite
Weinrich Minerals, Inc. Google Search for Arakiite

Ask about Arakiite 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 Español

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

Arakiite

(Zn,Mn++)(Mn++,Mg)12(Fe+++,Al)2(AsO3)(AsO4)2(OH)23
Dana No: 46.02.08.02 Strunz No: 08.BE.45
Locality:

Notes: