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Epistolite Mineral Data

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General Epistolite Information

Help on Chemical  Formula: Chemical Formula: (Na,[ ])2{(Na,Ti)4[Nb2(O,H2O)4Si4O14](OH,F)2}•2H2O
Help on Composition: Composition: Molecular Weight = 758.20 gm
   Sodium     11.49 %  Na   15.49 % Na2O
   Calcium     1.43 %  Ca    2.00 % CaO
   Titanium    0.25 %  Ti    0.42 % TiO2
   Manganese   0.29 %  Mn    0.37 % MnO
   Niobium    23.53 %  Nb   33.66 % Nb2O5
   Iron        0.29 %  Fe    0.42 % Fe2O3
   Silicon    14.82 %  Si   31.70 % SiO2
   Hydrogen    1.25 %  H    11.21 % H2O
   Oxygen     45.24 %  O
   Fluorine    1.40 %  F     1.40 % F
                -   %   F    -0.59 % -O=F2    
             ______        ______ 
             100.00 %       96.09 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Na3.79Ca0.27Mn2+0.04Nb1.92Ti0.04Fe3+0.04(Si2O7)2O2(OH)1.44F0.56�4(H2O)
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1897
Help on Locality: Locality: Tugtupagtakorfia, Kvanefield, and Taseq slope, Ilimaussag intrusion, Julianehaab area, southern Greenland. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for the Greek for "letter" in allusion to the flat, rectangular form and white color.
Help on Name Pronunciation: Name Pronunciation: Epistolite + Pronunciation Say EPISTOLITE
 

Epistolite Image

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  Epistolite

Comments: Plate-like crystals of pearly white epistolite to 2.7 cm.
Location: Ilimaussaq, Kvanefjeld, Greenland. Scale: 3.5 cm.
© John Veevaert

Epistolite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.7615:1:1.6793
Help on Cell Dimensions: Cell Dimensions: a = 5.46, b = 7.17, c = 12.041, Z = 1; alpha = 103.63°, beta = 96.01°, gamma = 89.98° V = 455.59 Den(Calc)= 2.76
Help on Crystal System: Crystal System: Triclinic - Pinacoidal H-M Symbol ( 1) Space Group: P1
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 4.33(1), 6.11(1), 2.72(0.8),
 

Physical Properties of Epistolite

Help on Cleavage: Cleavage: {001} Perfect, {110} Distinct
Help on Color: Color: White, Yellowish white, Gray, Light brown.
Help on Density: Density: 2.65 - 2.89, Average = 2.77
Help on Diaphaneity: Diaphaneity: Translucent
Help on Fracture: Fracture: Brittle - Generally displayed by glasses and most non-metallic minerals.
Help on Habit: Habit: Platy - Sheet forms (e.g. micas).
Help on Hardness: Hardness: 1-1.5 - Talc or a little harder
Help on Luster: Luster: Pearly
Help on Streak: Streak: white
 

Optical Properties of Epistolite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.006 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= -0.01 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2345,KPDmeas= 0.2337,KC= 0.2323
Ncalc = 1.62 - 1.67
Help on Optical Data: Optical Data: Biaxial (-), a=1.61, b=1.65, g=1.682, bire=0.0720, 2V(Calc)=80, 2V(Meas)=60.
 

Calculated Properties of Epistolite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.71 gm/cc
note: Specific Gravity of Epistolite =2.77 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0075468691
Boson Index = 0.9924531309
Help on Photoelectric: Photoelectric: PEEpistolite = 35.22 barns/electron
U=PEEpistolite x rElectron Density= 95.39 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Epistolite is Not Radioactive
 

Epistolite Classification

Help on  Dana Class: Dana Class: 56.02.07.01 (56)Sorosilicate Si2O7 Groups and O, OH, F. and H2O
  (56.02)with cations in [4] and/or >[4] coordination
  (56.02.07)Murmanite group
 
56.02.07.01 Epistolite (Na,[])2{(Na,Ti)4[Nb2(O,H2O)4Si4O14](OH,F)2}•2H2O P1 1
 
56.02.07.02 Murmanite (Na,[])2{(Na,Ti)4[Ti2(O,H2O)4Si4O14](OH,F)2}•2H2O P1 ? 1
 
56.02.07.03 Shkatulkalite! {(Na,Mn,Ca,[])4[Nb2(O,H2O)4Si4O14](OH,F)2}•2(H2O,[]) P 2,Pm,P 2/m Mono
Help on  Strunz Class: Strunz Class: 09.BE.30 09 - SILICATES (Germanates)
  09.B - Sorosilicates
  09.BE -Si2O7 groups with additional anions;
 
09.BE.30 Epistolite (Na,[])2{(Na,Ti)4[Nb2(O,H2O)4Si4O14](OH,F)2}•2H2O P1 1
 

Other Epistolite Information

Help on References: References: NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990, CanMin, 42:797) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)
Help on See Also: See Also: Links to other databases for Epistolite :
1 - Alkali-Nuts(English)
2 - Alkali-Nuts(Francais)
3 - Am. Min. Crystal Structure Database
4 - Athena
5 - EUROmin Project
6 - Ecole des Mines de Paris
7 - GeoScienceWorld
8 - Google Images
9 - Google Scholar
10 - Handbook of Mineralogy (MinSocAm)
11 - Handbook of Mineralogy (UofA)
12 - MinDAT
13 - Mineralienatlas (Deutsch)
14 - Online Mineral Museum
15 - QUT Mineral Atlas
16 - Ruff.Info

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

Epistolite

(Na,[ ])2{(Na,Ti)4[Nb2(O,H2O)4Si4O14](OH,F)2}•2H2O
Dana No: 56.02.07.01 Strunz No: 09.BE.30
Locality:

 

Notes:

 

 
   
 


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