Manjiroite Mineral Data

General Manjiroite Information

Chemical Formula:

(Na,K)(Mn++++,Mn++)8O16•n(H2O)

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

Empirical Formula:

Na_0.7K_0.2Mn⁴⁺_7.5Mn²⁺_0.3Al_0.1O₁₆•1.6(H₂O)

Environment:

Oxidation zone of metamorphosed bedded manganese deposits.

IMA Status:

Approved IMA 1967

Locality:

Kohare, Tachikawa, Kotamagawa, Kawai, and Takinosawa mines, Iwate Prefecture, Japan. Link to MinDat.org Location Data.

Name Origin:

Named for Manjiro Watanabe (1891-?), Emeritus Professor of Mineralogy, Tohoku University, Sendai, Japan.

Name Pronunciation:

Manjiroite + Pronunciation

Manjiroite Image

Images:

Manjiroite

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

Manjiroite Crystallography

Axial Ratios:

a:c = 1:0.28882

Cell Dimensions:

a = 9.916, c = 2.864, Z = 1; V = 281.61 Den(Calc)= 4.36

Crystal System:

Tetragonal - DipyramidalH-M Symbol (4/m) Space Group: I 4/m

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

By Intensity(I/I_o): 2.406(1), 7.017(0.98), 3.136(0.92),

Physical Properties of Manjiroite

Cleavage:

None

Color:

Brownish gray, Gray brown, Dark brown gray.

Density:

4.29

Diaphaneity:

Opaque

Fracture:

Conchoidal - Fractures developed in brittle materials characterized by smoothly curving surfaces, (e.g. quartz).

Habit:

Massive - Uniformly indistinguishable crystals forming large masses.

Hardness:

7 - Quartz

Luster:

Earthy (Dull)

Streak:

brownish black

Optical Properties of Manjiroite

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

Electron Density:

Bulk Density (Electron Density)=4.15 gm/cc
note: Specific Gravity of Manjiroite =4.36 gm/cc.

Fermion Index:

Fermion Index = 0.0001845889
Boson Index = 0.9998154111

Photoelectric:

PE_Manjiroite= 15.26 barns/electron
U=PE_Manjiroite x r_electron= 63.28 barns/cc.

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

Dana Class:

07.09.01.03 (07)Multiple Oxides

(07.09)Dana Type

(07.09.01)Cryptomelane Group (Hard black, fine-grained)

07.09.01.01 Hollandite Ba(Mn,Mn)8O16 I2/m 2/m

07.09.01.02 Cryptomelane K(Mn,Mn)8O16 I2/m 2/m

07.09.01.03 Manjiroite (Na,K)(Mn,Mn)8O16•n(H2O) I 4/m 4/m

07.09.01.04 Coronadite Pb(Mn,Mn)8O16 I2/m 2/m

07.09.01.05 Strontiomelane! SrMn6Mn2O16 P 2₁/m 2/m

07.09.01.06 Henrymeyerite! BaFeTi7O16 I 4/m 4/m

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

References:

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

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

Search for Manjiroite using:

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

Visit our Advertisers for Manjiroite :

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

Ask about Manjiroite 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 Manjiroite Specimen Label here :

Manjiroite

(Na,K)(Mn++++,Mn++)8O16•n(H2O)
Dana No: 07.09.01.03 Strunz No: 04.DK.05
Locality:

Notes: