Bykovaite Mineral Data

General Bykovaite Information

Chemical Formula:

BaNa{(Na,Ti)4[(Ti,Nb)2(OH,O)3Si4O14](OH,F)2}•3H2O

Composition:

Molecular Weight = 824.26 gm

Potassium 0.57 % K 0.69 % K₂O

Barium 11.83 % Ba 13.21 % BaO

Sodium 9.87 % Na 13.31 % Na₂O

Strontium 0.53 % Sr 0.63 % SrO

Calcium 0.15 % Ca 0.20 % CaO

Titanium 11.33 % Ti 18.90 % TiO₂

Manganese 1.73 % Mn 2.24 % MnO

Niobium 7.44 % Nb 10.64 % Nb₂O₅

Aluminum 0.07 % Al 0.12 % Al₂O₃

Iron 0.20 % Fe 0.26 % FeO

Silicon 13.56 % Si 29.01 % SiO₂

Hydrogen 1.12 % H 9.98 % H₂O

Oxygen 40.20 % O

Fluorine 1.41 % F 1.41 % F

- % F -0.59 % -O=F₂

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Na_0.47K_0.12Sr_0.05Na_3.07Ti_0.61Mn²⁺_0.26Ca_0.03Fe²⁺_0.03Ti_1.34Nb_0.66Si_3.98Al_0.02O₁₄(OH)_3.13 F_0.61O_0.58ï¿½3(H₂O)

Environment:

Pegmatite vein consisting of a central ussingitic core surrounded by a zone of mostly microcline and aegirine at the margins, and lies in poikilitic nepheline-sodalite syenite. Hete rophyllosilicate pseudomorphous after

IMA Status:

Approved IMA 2003 (Dana # Added)

Locality:

Alluaiv, Lovozero Massif, Kola, Russia Link to MinDat.org Location Data.

Name Origin:

Named to honor analytical chemist Alexandra Vasilyevna Bykova (1917-2001), who first discovered that bornemanite could be transformed to a synthetic form of bykovaite upon treatment with water.

Synonym:

IMA2003-044

Bykovaite Image

Images:

Bykovaite

Comments: Creamy transparent silky bykovaite crystals in matrix.
Location: Mt. Alluaiv, Lovozero, Kola, Russia. Scale: Not Given.
© Diederik Visser

Bykovaite Crystallography

Axial Ratios:

a:b:c =0.7733:1:7.0956

Cell Dimensions:

a = 5.552, b = 7.179, c = 50.94, Z = 4; beta = 91.1° V = 2,029.98 Den(Calc)= 2.70

Crystal System:

Monoclinic - Sphenoidal H-M Symbol (2) Space Group: I11b

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

By Intensity(I/I_o): 25.5(1), 3.17(0.74), 8.48(0.72),2.763(0.2), 2.11(0.14), 3.44(0.14), 12.68(0.14), 5.11(0.11),

Physical Properties of Bykovaite

Cleavage:

{001} Perfect, {100} Imperfect

Color:

Creamy yellow, Pale yellow.

Density:

2.98

Diaphaneity:

Semitransparent

Fracture:

Brittle - Splintery - Brittle fracture leaving splintery fragments.

Habit:

Spherical - Spherical, rounded aggregates.

Hardness:

3 - Calcite

Luster:

Silky

Streak:

white

Optical Properties of Bykovaite

Gladstone-Dale:

CI meas= 0.071 (Fair) - where the CI = (1-KPDmeas/KC)
CI calc= -0.025 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.254,KPDmeas= 0.2301,KC= 0.2477
Ncalc = 1.67 - 1.74

Optical Data:

Biaxial (+), a=1.668, b=1.679, g=1.71, bire=0.0420

Calculated Properties of Bykovaite

Electron Density:

Bulk Density (Electron Density)=2.60 gm/cc
note: Specific Gravity of Bykovaite =2.70 gm/cc.

Fermion Index:

Fermion Index = 0.04
Boson Index = 0.96

Photoelectric:

PE_Bykovaite= 63.92 barns/electron
U=PE_Bykovaite x r_electron= 166.24 barns/cc.

Radioactivity:

GRapi = 7.89 (Gamma Ray American Petroleum Institute Units)
Concentration of Bykovaite per GRapi unit = 12.67 (%)

Estimated Radioactivity from Bykovaite - barely detectable

Bykovaite Classification

Dana Class:

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

(56.04)with [Si2O7] with phosphate, water

(56.04.02)Bornemanite Group

56.04.02.01 Bornemanite BaNa3{(Na,Ti)4[(Ti,Nb)2O2Si4O14](F,OH)2}•PO4 I11b m

56.04.02.02 Bykovaite! BaNa{(Na,Ti)4[(Ti,Nb)2(OH,O)3Si4O14](OH,F)2}•3H2O I11b 2

Strunz Class:

09.BE.50 09 - SILICATES (Germanates)

09.B - Sorosilicates

09.BE -Si2O7 groups with additional anions;

09.BE.50 Bornemanite BaNa3{(Na,Ti)4[(Ti,Nb)2O2Si4O14](F,OH)2}•PO4 I11b m

09.BE.50 Shkatulkalite! {(Na,Mn,Ca,[])4[Nb2(O,H2O)4Si4O14](OH,F)2}•2(H2O,[]) P 2,Pm,P 2/m Mono

09.BE.50 Bykovaite! BaNa{(Na,Ti)4[(Ti,Nb)2(OH,O)3Si4O14](OH,F)2}•3H2O I11b 2

Other Bykovaite Information

References:

NAME( AmMin, v91, p1452) PHYS. PROP.(AmMin, v91, p1452) OPTIC PROP.(AmMin, v91, p1452)

See Also:

Links to other databases for Bykovaite :
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 Bykovaite Specimen Label here :

Bykovaite

BaNa{(Na,Ti)4[(Ti,Nb)2(OH,O)3Si4O14](OH,F)2}•3H2O
Dana No: 56.04.02.02 Strunz No: 09.BE.50
Locality:

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