Tokyoite Mineral Data

General Tokyoite Information

Chemical Formula:

Ba2Mn(VO4)2(OH)

Composition:

Molecular Weight = 565.05 gm

Barium 46.66 % Ba 52.10 % BaO

Sodium 0.08 % Na 0.11 % Na₂O

Strontium 0.16 % Sr 0.18 % SrO

Calcium 0.07 % Ca 0.10 % CaO

Manganese 7.88 % Mn 11.32 % Mn₂O₃

Aluminum 0.05 % Al 0.09 % Al₂O₃

Vanadium 17.94 % V 32.03 % V₂O₅

Iron 1.68 % Fe 2.40 % Fe₂O₃

Silicon 0.05 % Si 0.11 % SiO₂

Hydrogen 0.18 % H 1.59 % H₂O

Oxygen 25.26 % O

______ ______

100.00 % 100.03 % = TOTAL OXIDE

Empirical Formula:

Ba_1.92Na_0.02Sr_0.01Ca_0.01Mn³⁺_0.81Fe³⁺_0.17Al_0.01V⁵⁺_1.99Si_0.01O_7.92(OH)

Environment:

Found in an outcrop of an abandoned Mn ore deposit in the Shiromaru mine. The ore deposit occurs in chert blocks enclosed in middle to upper Jurassic sandstones. Mn-dominant analogu e of gamagarite

IMA Status:

Approved IMA 2003 (Dana # Added)

Locality:

Shiromaru Mine, Okutama, Tama district, Tokyo Prefecture, Kanto Region, Honshu Island, Japan. Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Synonym:

IMA2003-036

Tokyoite Image

Images:

Tokyoite

Comments: Metallic reddish brown crystals of tokyoite (< 0.3 mm) on dark gray braunite matrix.
Location: Gambatesa mine, Graveglia Valley, Genova, Italy. Scale: Picture size 4 mm.
© Tom Loomis / Dakota Matrix

Tokyoite Crystallography

Axial Ratios:

a:b:c =1.4845:1:1.2871

Cell Dimensions:

a = 9.1, b = 6.13, c = 7.89, Z = 2; beta = 112.2° V = 407.50 Den(Calc)= 4.60

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 2₁/m

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

By Intensity(I/I_o): 3.31(1)(112 ), 2.8(0.62)(121,300 ), 2.71(0.4)(311 ), 3.46(0.26)(210 )3.08(0.2)(020 ), 2.9(0.19)(120 ), 2.16(0.18)(321 )1.963(0.15)(204 3.73(0.15)(111 ),

Physical Properties of Tokyoite

Cleavage:

None

Color:

Reddish black.

Diaphaneity:

Translucent

Fracture:

Unknown - Minerals too small to observe fractures.

Habit:

Irregular Grains - Occurs as splotchy, anhedral crystals forming inclusions in other minerals or rocks.

Hardness:

4-4.5 - Between Fluorite and Apatite

Luster:

Sub Metallic

Streak:

dark brownish-red

Optical Properties of Tokyoite

Gladstone-Dale:

CI calc= 0.019 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2196,KC= 0.2237
Ncalc = 2.03

Optical Data:

Biaxial (?), a=1.99, g=2.03, bire=0.0400

Reflectivity

**Standardized Intensity (100%) Reflection Spectra of Tokyoite in Air**
λ	R₁	R₂	∑ R₁(λ)	∑ R₂(λ)
470 nm	12.80	13.20
546 nm	12.30	12.60
589 nm	12.20	12.50
650 nm	12.50	12.60

**Standardized Intensity (100%) Reflection Spectra of Tokyoite in Oil**
λ	R₁	R₂	∑ R₁(λ)	∑ R₂(λ)
470 nm	3.30	3.50
546 nm	3.10	3.40
589 nm	3.10	3.60
650 nm	3.60	4.30

**Calculated Relative Intensity Colors of Tokyoite in Air**
Relative Intensity	0%	80%	100%	160%	240%	320%	400%	480%	560%	640%	710%
R₁
R₂

**Calculated Relative Intensity Colors of Tokyoite in Oil**
Relative Intensity	0%	100%	200%	300%	400%	500%	600%	700%	800%	900%	1000%
R₁
R₂

Calculated Properties of Tokyoite

Electron Density:

Bulk Density (Electron Density)=4.09 gm/cc
note: Specific Gravity of Tokyoite =4.60 gm/cc.

Fermion Index:

Fermion Index = 0.08
Boson Index = 0.92

Photoelectric:

PE_Tokyoite= 216.84 barns/electron
U=PE_Tokyoite x rElectron Density= 887.54 barns/cc.

Radioactivity:

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

Tokyoite Classification

Dana Class:

41.10.04.04 (41)Anhydrous Phosphates, etc. Containing Hydroxyl or Halogen

(41.10)where (A++ B++)3 (XO4)2 Zq

(41.10.04)Goedkenite Group

41.10.04.01 Goedkenite (Sr,Ca)2Al(PO4)2(OH) P 2₁/m 2/m

41.10.04.02 Bearthite Ca2Al(PO4)2(OH) P 2₁/m 2/m

41.10.04.03 Gamagarite Ba2(Fe,Mn)(VO4)2(OH) P 2₁/m 2/m

41.10.04.04 Tokyoite! Ba2Mn(VO4)2(OH) P 2₁/m 2/m

Strunz Class:

08.BG.05 08 - PHOSPHATES, ARSENATES, VANADATES

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

08.BG -With medium-sized and large cations, (OH, etc.):RO4 = 0.5:1

08.BG.05 Arsenbrackebuschite Pb2(Fe,Zn)(AsO4)2•(H2O) P 2₁/m 2/m

08.BG.05 Bearthite Ca2Al(PO4)2(OH) P 2₁/m 2/m

08.BG.05 Arsentsumebite Pb2Cu(AsO4)(SO4)(OH) P 2₁/m 2/m

08.BG.05 Brackebuschite Pb2(Mn,Fe)(VO4)2(OH) P 2₁/m 2/m

08.BG.05 Feinglosite! Pb2(Zn,Fe)[(As,S)O4]2•(H2O) P 2₁,P 2₁/m Mono

08.BG.05 Gamagarite Ba2(Fe,Mn)(VO4)2(OH) P 2₁/m 2/m

08.BG.05 Goedkenite (Sr,Ca)2Al(PO4)2(OH) P 2₁/m 2/m

08.BG.05 Tsumebite Pb2Cu(PO4)(SO4)(OH) P 2₁/m 2/m

08.BG.05 Calderonite! Pb2Fe(VO4)2(OH) P 2₁/m 2/m

08.BG.05 Bushmakinite! Pb2Al(PO4)(VO4)(OH) P 2₁/m 2/m

08.BG.05 Tokyoite! Ba2Mn(VO4)2(OH) P 2₁/m 2/m

Other Tokyoite Information

References:

NAME( AmMin, v90, p1468) PHYS. PROP.(AmMin, v90, p1468) OPTIC PROP.(AmMin, v90, p1468)

See Also:

Links to other databases for Tokyoite :
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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Tokyoite

Ba2Mn(VO4)2(OH)
Dana No: 41.10.04.04 Strunz No: 08.BG.05
Locality:

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