Tantalite-(Mn) Mineral Data

General Tantalite-(Mn) Information

Chemical Formula:

MnTa2O6

Composition:

Molecular Weight = 512.83 gm

Tantalum 70.57 % Ta 86.17 % Ta₂O₅

Manganese 10.71 % Mn 13.83 % MnO

Oxygen 18.72 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Mn²⁺Ta₂O₆

Environment:

Pegmatites and alluvial deposits.

IMA Status:

Valid Species (Pre-IMA) 1887

Locality:

Custer and Pennington Cos., South Dakota, USA. Link to MinDat.org Location Data.

Name Origin:

Named after its chemical composition containing manganese and tantalum.

Synonym:

Coltan

Manganotantalite - Renamed to Tantalite-(Mn) by Mineralogical Record, v39 (2008), p 131

Tantalite-(Mn) Image

Images:

Tantalite-(Mn)

Comments: Floater crystal of doubly terminated, brilliant, with a little red tint manganotantalite.
Location: Pech, Kunar, Afganistan. Scale: 5.5 x 7 cm.
© Fabre Minerals

Images:

Calciotantite Tantalite-(Mn)

Comments: SEM image showing calciotantite (CT), manganotatntalite (MTT), microlite (MT) and lithiowodginite (LW) association.
Location: Granitic pegmatites, Kalba, Kazakhstan. Scale: Scale bar 100 µm and 10 µm.
© Diederik Visser

Tantalite-(Mn) Crystallography

Axial Ratios:

a:b:c =0.399:1:0.3523

Cell Dimensions:

a = 5.772, b = 14.465, c = 5.097, Z = 4; V = 425.56 Den(Calc)= 8.00

Crystal System:

Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Pcan

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

By Intensity(I/I_o): 2.99(1), 3.69(0.9), 2.41(0.7),

Physical Properties of Tantalite-(Mn)

Cleavage:

{100} Imperfect

Color:

Black, Brown.

Density:

8.1

Diaphaneity:

Opaque

Fracture:

Brittle - Uneven - Very brittle fracture producing uneven fragments.

Habit:

Crystalline - Fine - Occurs as well-formed fine sized crystals.

Habit:

Disseminated - Occurs in small, distinct particles dispersed in matrix.

Habit:

Massive - Granular - Common texture observed in granite and other igneous rock.

Hardness:

6-6.5 - Orthoclase-Pyrite

Luminescence:

Non-fluorescent.

Luster:

Sub Metallic

Streak:

brown

Optical Properties of Tantalite-(Mn)

Gladstone-Dale:

CI meas= 0.047 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= 0.035 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1519,KPDmeas= 0.15,KC= 0.1574
Ncalc = 2.26 - 2.27

Optical Data:

Biaxial (+), a=2.14-2.19, b=2.15-2.25, g=2.22-2.34, bire=0.0800-0.1500

Pleochroism (x):

red.

Pleochroism (y):

red brown.

Pleochroism (z):

orange.

Reflectivity

**Standardized Intensity (100%) Reflection Spectra of Tantalite-(Mn) in Air**
λ	R₁	R₂	∑ R₁(λ)	∑ R₂(λ)
400 nm	15.50	16.40
420 nm	15.10	16.00
440 nm	14.80	15.70
460 nm	14.60	15.40
480 nm	14.30	15.20
500 nm	14.10	15.00
520 nm	13.90	14.80
540 nm	13.80	14.70
560 nm	13.60	14.50
580 nm	13.60	14.40
600 nm	13.50	14.40
620 nm	13.50	14.30
640 nm	13.40	14.30
660 nm	13.40	14.30
680 nm	13.30	14.20
700 nm	13.30	14.20

**Calculated Relative Intensity Colors of Tantalite-(Mn) in Air**
Relative Intensity	0%	70%	100%	140%	210%	280%	350%	420%	490%	560%	630%	650%
R₁
R₂

Calculated Properties of Tantalite-(Mn)

Electron Density:

Bulk Density (Electron Density)=6.83 gm/cc
note: Specific Gravity of Tantalite-(Mn) =8.00 gm/cc.

Fermion Index:

Fermion Index = 0.0001745329
Boson Index = 0.9998254671

Photoelectric:

PE_{Tantalite-(Mn)}= 853.94 barns/electron
U=PE_{Tantalite-(Mn)} x rElectron Density=5,834.70 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Tantalite-(Mn) is Not Radioactive

Tantalite-(Mn) Classification

Dana Class:

08.03.02.03 (08)Multiple Oxides with Nb, Ta, and Ti

(08.03)where A (B2O6)

(08.03.02)Tantalite - Columbite Series

08.03.02.01 Tantalite-(Fe) FeTa2O6 Pcan 2/m 2/m 2/m

08.03.02.02 Columbite-(Fe) FeNb2O6 Pcan 2/m 2/m 2/m

08.03.02.03 Tantalite-(Mn) MnTa2O6 Pcan 2/m 2/m 2/m

08.03.02.04 Columbite-(Mn) (Mn,Fe)(Nb,Ta)2O6 Pcan 2/m 2/m 2/m

08.03.02.05 Columbite-(Mg) (Mg,Fe,Mn)(Nb,Ta)2O6 Pcan 2/m 2/m 2/m

08.03.02.06 Tantalite-(Mg)! (Mg,Fe)(Ta,Nb)2O6 P bcn 2/m 2/m 2/m

Strunz Class:

04.DB.35 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.D - Metal:Oxygen = 1:2 and similar

04.DB -With medium-sized cations; chains of edge-sharing octahedra

04.DB.35 Columbite-(Mg) (Mg,Fe,Mn)(Nb,Ta)2O6 Pcan 2/m 2/m 2/m

04.DB.35 Tantalite-(Fe) FeTa2O6 Pcan 2/m 2/m 2/m

04.DB.35 Columbite-(Fe) FeNb2O6 Pcan 2/m 2/m 2/m

04.DB.35 Columbite-(Mn) (Mn,Fe)(Nb,Ta)2O6 Pcan 2/m 2/m 2/m

04.DB.35 Qitianlingite Fe2Nb2WO10 P bcn 2/m 2/m 2/m

04.DB.35 Tantalite-(Mn) MnTa2O6 Pcan 2/m 2/m 2/m

04.DB.35 Tantalite-(Mg)! (Mg,Fe)(Ta,Nb)2O6 P bcn 2/m 2/m 2/m

Other Tantalite-(Mn) Information

References:

NAME( Duda&Rejl90) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic3)

See Also:

Links to other databases for Tantalite-(Mn) :
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 Tantalite-(Mn) Specimen Label here :

Tantalite-(Mn)

MnTa2O6
Dana No: 08.03.02.03 Strunz No: 04.DB.35
Locality:

Notes:

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