Strakhovite Mineral Data

General Strakhovite Information

Chemical Formula:

NaBa3(Mn++,Mn+++)4Si6O19(OH)3

Composition:

Molecular Weight = 1,178.25 gm

Barium 34.97 % Ba 39.04 % BaO

Sodium 1.95 % Na 2.63 % Na₂O

Manganese 18.65 % Mn 18.06 % MnO / 7.38 % MnO₂

Silicon 14.30 % Si 30.60 % SiO₂

Hydrogen 0.26 % H 2.29 % H₂O

Oxygen 29.87 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

NaBa₃Mn²⁺₃Mn⁴⁺Si₆O₁₉(OH)₃

Environment:

At the contact between braunite ore and alkali basalt.

IMA Status:

Approved IMA 1994

Locality:

The Ir-Nimi manganese deposit, Taikan Ridge, Far East, Russia. Link to MinDat.org Location Data.

Name Origin:

For N. M Strakhov (1900-1978), for his contributions to the study of sedimentary ore deposits and phosphorites.

Name Pronunciation:

Strakhovite + Pronunciation

Synonym:

ICSD 39582

IMA1993-005

PDF 46-1421

Strakhovite Image

Images:

Strakhovite

Comments: Dark green vitreous massive strakhovite with inset image of sample.
Location: Dzhavodi Area, Ir-Nimi manganese deposit, Taikan Ridge, Khabarovskiy Kray, Far-Eastern Region, Russia. Scale: See Image.
© Rruff Database

Strakhovite Crystallography

Axial Ratios:

a:b:c =1.9093:1:0.5854

Cell Dimensions:

a = 23.42, b = 12.266, c = 7.181, Z = 4; V = 2,062.88 Den(Calc)= 3.79

Crystal System:

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

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

By Intensity(I/I_o): 2.655(1), 2.999(1), 3.303(0.9),

Physical Properties of Strakhovite

Cleavage:

{110} Imperfect

Color:

Black, Greenish black, Dark olive green.

Density:

3.86

Diaphaneity:

Translucent

Fracture:

Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.

Habit:

Granular - Generally occurs as anhedral to subhedral crystals in matrix.

Hardness:

5-6 - Between Apatite and Orthoclase

Luminescence:

Non-fluorescent.

Luster:

Vitreous - Greasy

Streak:

green

Optical Properties of Strakhovite

Gladstone-Dale:

CI meas= -0.099 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.119 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2138,KPDmeas= 0.2099,KC= 0.1911
Ncalc = 1.72 - 1.74

Optical Data:

Biaxial (+), a=1.767, b=1.793, g=1.871, bire=0.1040, 2V(Calc)=64, 2V(Meas)=60-65. Dispersion strong, r > v.

Pleochroism (x):

light green or light green.

Pleochroism (y):

green or green.

Pleochroism (z):

dark olive green or brown.

Calculated Properties of Strakhovite

Electron Density:

Bulk Density (Electron Density)=3.55 gm/cc
note: Specific Gravity of Strakhovite =3.86 gm/cc.

Fermion Index:

Fermion Index = 0.06
Boson Index = 0.94

Photoelectric:

PE_Strakhovite= 157.97 barns/electron
U=PE_Strakhovite x rElectron Density= 561.00 barns/cc.

Radioactivity:

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

Strakhovite Classification

Dana Class:

64.03.02.01 (64)Cyclosilicates

(64.03)4-membered rings with [Si2O7] dimers

(64.03.02)Dana Group

64.03.02.01 Strakhovite NaBa3(Mn,Mn)4Si6O19(OH)3 P nma 2/m 2/m 2/m

Strunz Class:

09.CF.20 09 - SILICATES (Germanates)

09.C - Cyclosilicates

09.CF -[Si4O12]8- 4-membered single rings, with insular complex anions

09.CF.20 Strakhovite NaBa3(Mn,Mn)4Si6O19(OH)3 P nma 2/m 2/m 2/m

Other Strakhovite Information

References:

NAME( MinRec) PHYS. PROP.(Am.Min.,Vol.81,1996) OPTIC PROP.(MinRec)

See Also:

Links to other databases for Strakhovite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - GeoScienceWorld
5 - Google Images
6 - Google Scholar
7 - MinDAT
8 - Mineralienatlas (Deutsch)
9 - Online Mineral Museum
10 - QUT Mineral Atlas
11 - Ruff.Info
12 - WWW-MINCRYST

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Print or Cut-and-Paste your Strakhovite Specimen Label here :

Strakhovite

NaBa3(Mn++,Mn+++)4Si6O19(OH)3
Dana No: 64.03.02.01 Strunz No: 09.CF.20
Locality:

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