Manganilvaite Mineral Data

General Manganilvaite Information

Chemical Formula:

CaFe++Fe+++(Mn,Fe++)(Si2O7)O(OH)

Composition:

Molecular Weight = 407.15 gm

Calcium 9.25 % Ca 12.95 % CaO

Magnesium 0.30 % Mg 0.49 % MgO

Manganese 10.39 % Mn 13.42 % MnO

Aluminum 0.20 % Al 0.38 % Al₂O₃

Iron 30.45 % Fe 21.70 % FeO / 19.41 % Fe₂O₃

Silicon 13.80 % Si 29.51 % SiO₂

Hydrogen 0.25 % H 2.21 % H₂O

Oxygen 35.37 % O

______ ______

100.00 % 100.08 % = TOTAL OXIDE

Empirical Formula:

Ca_0.94Mn²⁺_0.06Fe²⁺_0.94Mg_0.05Fe³⁺_0.99Al_0.03Mn²⁺_0.71Fe²⁺_0.29(Si₂O₇)O(OH)

Environment:

Marble-hosted skarn-type orebodies at the Ossikovo and Mogilata deposits (Madan ore district) and the Govedarnika deposit (Laki district). Mn-dominant analogue of ilvaite.

IMA Status:

Approved IMA 2002 (Dana # Added)

Locality:

Pb-Zn skarn deposits in the Rhodope Mountains, Bulgaria Link to MinDat.org Location Data.

Name Origin:

Named as the Mn analogue of ilvaite with which it forms a continuous solid solution.

Synonym:

IMA2002-016

Manganilvaite Image

Images:

Manganilvaite Manganilvaite

Comments: Small, black, very bright crystals of manganilvaite on a matrix of clear quartz, white calcite, and tiny brassy pyrite crystals.
Location: Daye mining area, Hubei, China. Scale: 6 x 5.6 x 3.7 cm.
© Fabre Minerals

Manganilvaite Crystallography

Axial Ratios:

a:b:c =1.4715:1:0.6607

Cell Dimensions:

a = 13.025, b = 8.8514, c = 5.8486, Z = 4; beta = 90.167° V = 674.28 Den(Calc)= 4.01

Crystal System:

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

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

By Intensity(I/I_o): 2.718(1)(112,112 ), 2.848(0.9)(401,401 2.875(0.85)(130 2.687(0.7)(230), 1.475(0.48)(060,252,523 2.18(0.48)(140 2.111(0.47)(322.412,412 1.716(0.39)(720 1.49

Physical Properties of Manganilvaite

Cleavage:

{100} Distinct

Color:

Black.

Density:

3.92

Diaphaneity:

Opaque

Fracture:

Brittle - Uneven - Very brittle fracture producing uneven fragments.

Habit:

Pyramidal - Crystals are shaped like pyramids.

Habit:

Striated - Parallel lines on crystal surface or cleavage face.

Hardness:

5.5-6 - Knife Blade-Orthoclase

Luster:

Vitreous (Glassy)

Streak:

brownish Black

Optical Properties of Manganilvaite

Optical Data:

NCalc= 1.91 - from Gladstone-Dale relationship (KC = 0.2262) where Ncalc=Dcalc*KC+1
NCalc= 1.89 - from Gladstone-Dale relationship (KC = 0.2262) where Ncalc=Dmeas*KC+1

RL Anisotrophism:

Strong in blue-grayish.

RL Color:

Gray to bluish gray with red internal reflections.

RL Pleochroism:

Bluish gray to lilac brown.

Reflectivity

**Standardized Intensity (100%) Reflection Spectra of Manganilvaite in Air**
λ	R₁	R₂	∑ R₁(λ)	∑ R₂(λ)
460 nm	8.30	10.00
540 nm	7.50	9.80
580 nm	7.00	9.70
640 nm	6.10	9.50

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

Calculated Properties of Manganilvaite

Electron Density:

Bulk Density (Electron Density)=3.90 gm/cc
note: Specific Gravity of Manganilvaite =4.01 gm/cc.

Fermion Index:

Fermion Index = 0.01
Boson Index = 0.99

Photoelectric:

PE_{Manganilvaite}= 13.47 barns/electron
U=PE_{Manganilvaite} x rElectron Density= 52.49 barns/cc.

Radioactivity:

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

Manganilvaite Classification

Dana Class:

56.02.03.06 (56)Sorosilicate Si2O7 Groups and O, OH, F. and H2O

(56.02)with cations in [4] and/or >[4] coordination

(56.02.03)Lawsonite - Ilvaite group

56.02.03.01 Lawsonite CaAl2Si2O7(OH)2•(H2O) Ccmm 2/m 2/m 2/m

56.02.03.02 Hennomartinite SrMn2Si2O7(OH)2•(H2O) C mcm 2/m 2/m 2/m

56.02.03.03 Ilvaite CaFe2FeSi2O7O(OH) Pbnm 2/m 2/m 2/m

56.02.03.04 Noelbensonite! BaMn2(Si2O7)(OH)2•(H2O) C mcm 2/m 2/m 2/m

56.02.03.05 Itoigawaite! SrAl2Si2O7(OH)2•(H2O) C mcm 2/m 2/m 2/m

56.02.03.06 Manganilvaite! CaFeFe(Mn,Fe)(Si2O7)O(OH) P 2₁/a 2/m

Strunz Class:

09.BE.07 09 - SILICATES (Germanates)

09.B - Sorosilicates

09.BE -Si2O7 groups with additional anions;

09.BE.07 Ilvaite CaFe2FeSi2O7O(OH) Pbnm 2/m 2/m 2/m

09.BE.07 Manganilvaite! CaFeFe(Mn,Fe)(Si2O7)O(OH) P 2₁/a 2/m

Other Manganilvaite Information

References:

NAME( AmMin, v91, p712) PHYS. PROP.(AmMin, v91, p712) OPTIC PROP.(AmMin, v91, p712)

See Also:

Links to other databases for Manganilvaite :
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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Manganilvaite

CaFe++Fe+++(Mn,Fe++)(Si2O7)O(OH)
Dana No: 56.02.03.06 Strunz No: 09.BE.07
Locality:

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