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Manjiroite Mineral Data

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General Manjiroite Information

Help on Chemical  Formula: Chemical Formula: (Na,K)(Mn++++,Mn++)8O16•n(H2O)
Help on Composition: Composition: Molecular Weight = 739.94 gm
   Potassium   1.06 %  K     1.27 % K2O
   Sodium      2.17 %  Na    2.93 % Na2O
   Manganese  57.91 %  Mn    2.88 % MnO / 88.12 % MnO2
   Aluminum    0.36 %  Al    0.69 % Al2O3
   Hydrogen    0.44 %  H     3.90 % H2O
   Oxygen     38.06 %  O
             ______        ______ 
             100.00 %       99.78 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Na0.7K0.2Mn4+7.5Mn2+0.3Al0.1O16•1.6(H2O)
Help on Environment: Environment: Oxidation zone of metamorphosed bedded manganese deposits.
Help on IMA Status: IMA Status: Approved IMA 1967
Help on Locality: Locality: Kohare, Tachikawa, Kotamagawa, Kawai, and Takinosawa mines, Iwate Prefecture, Japan. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Manjiro Watanabe (1891-?), Emeritus Professor of Mineralogy, Tohoku University, Sendai, Japan.
Help on Name Pronunciation: Name Pronunciation: Manjiroite + Pronunciation Say MANJIROITE

Manjiroite Image

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Comments: Dark brownish black massive sample of manjiroite.
Location: Arizona, USA. Scale: 3.8 X 5.6 cm.
© John Veevaert

Manjiroite Crystallography

Help on Axial Ratios: Axial Ratios: a:c = 1:0.28882
Help on Cell Dimensions: Cell Dimensions: a = 9.916, c = 2.864, Z = 1; V = 281.61 Den(Calc)= 4.36
Help on Crystal System: Crystal System: Tetragonal - Dipyramidal H-M Symbol (4/m) Space Group: I 4/m
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.406(1), 7.017(0.98), 3.136(0.92),

Physical Properties of Manjiroite

Help on Cleavage: Cleavage: None
Help on Color: Color: Brownish gray, Gray brown, Dark brown gray.
Help on Density: Density: 4.29
Help on Diaphaneity: Diaphaneity: Opaque
Help on Fracture: Fracture: Conchoidal - Fractures developed in brittle materials characterized by smoothly curving surfaces, (e.g. quartz).
Help on Habit: Habit: Massive - Uniformly indistinguishable crystals forming large masses.
Help on Hardness: Hardness: 7 - Quartz
Help on Luster: Luster: Earthy (Dull)
Help on Streak: Streak: brownish black

Optical Properties of Manjiroite

Help on Optical Data: Optical Data: NCalc= 2.64 - from Gladstone-Dale relationship (KC = 0.3756) where Ncalc=Dcalc*KC+1
NCalc= 2.61 - from Gladstone-Dale relationship (KC = 0.3756) where Ncalc=Dmeas*KC+1

Calculated Properties of Manjiroite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=4.15 gm/cc
note: Specific Gravity of Manjiroite =4.36 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0001845889
Boson Index = 0.9998154111
Help on Photoelectric: Photoelectric: PEManjiroite = 15.26 barns/electron
U=PEManjiroite x relectron= 63.28 barns/cc.
Help on Radioactivity: Radioactivity:

GRapi = 14.49 (Gamma Ray American Petroleum Institute Units)
Concentration of Manjiroite per GRapi unit = 6.90 (%)

Estimated Radioactivity from Manjiroite - barely detectable


Manjiroite Classification

Help on  Dana Class: Dana Class: (07)Multiple Oxides
  (07.09)Dana Type
  (07.09.01)Cryptomelane Group (Hard black, fine-grained) Hollandite Ba(Mn,Mn)8O16 I2/m 2/m Cryptomelane K(Mn,Mn)8O16 I2/m 2/m Manjiroite (Na,K)(Mn,Mn)8O16•n(H2O) I 4/m 4/m Coronadite Pb(Mn,Mn)8O16 I2/m 2/m Strontiomelane! SrMn6Mn2O16 P 21/m 2/m Henrymeyerite! BaFeTi7O16 I 4/m 4/m
Help on  Strunz Class: Strunz Class: 04.DK.05 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate
  04.D - Metal:Oxygen = 1:2 and similar
  04.DK -With large (� medium-sized) cations; tunnel structures
04.DK.05 Akaganeite Fe(O,OH,Cl) I2/m 2/m
04.DK.05 Ankangite Ba(Ti,V,Cr)8O16 I 4/m 4/m
04.DK.05 Coronadite Pb(Mn,Mn)8O16 I2/m 2/m
04.DK.05 Hollandite Ba(Mn,Mn)8O16 I2/m 2/m
04.DK.05 Manjiroite (Na,K)(Mn,Mn)8O16•n(H2O) I 4/m 4/m
04.DK.05 Mannardite BaTi6V2O16•(H2O) I 41/a 4/m
04.DK.05 Redledgeite BaTi6Cr2O16•(H2O) I 41/a 4/m
04.DK.05 Priderite (K,Ba)(Ti,Fe)8O16 I 4/m 4/m
04.DK.05 Henrymeyerite! BaFeTi7O16 I 4/m 4/m

Other Manjiroite Information

Help on References: References: NAME( AntBidBlaNic3) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990)
Help on See Also: See Also: Links to other databases for Manjiroite :
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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Dana No: Strunz No: 04.DK.05





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