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Barrerite Mineral Data

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General Barrerite Information

Help on Chemical  Formula: Chemical Formula: (Na,K,Ca)2Al2Si7O18•6(H2O)
Help on Composition: Composition: Molecular Weight = 2,680.57 gm
   Potassium   1.55 %  K     1.86 % K2O
   Sodium      4.67 %  Na    6.30 % Na2O
   Calcium     1.26 %  Ca    1.76 % CaO
   Magnesium   0.15 %  Mg    0.26 % MgO
   Aluminum    8.24 %  Al   15.58 % Al2O3
   Iron        0.02 %  Fe    0.03 % FeO
   Silicon    23.80 %  Si   50.93 % SiO2
   Hydrogen    1.94 %  H    17.33 % H2O
   Oxygen     58.36 %  O
             ______        ______ 
             100.00 %       94.03 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Na5.45K1.06Ca0.84Mg0.17Al8.19Fe2+0.01Si22.72O72�25.78(H2O)
Help on Environment: Environment: On the walls of large fractures in deeply weathered andesitic and rhyolitic lavas.
Help on IMA Status: IMA Status: Approved IMA 1974
Help on Locality: Locality: Found near Capo Pula, below South Efisio Tower, Nora, Sardinia, Italy. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: For Richard Maling Barrer (1910- ), New Zealand-born British teacher ad student of the chemistry of zeolites.
Help on Name Pronunciation: Name Pronunciation: Barrerite + Pronunciation Say BARRERITE
Help on Synonym: Synonym: ICSD 4396
  PDF 29-1185

Barrerite Image

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Comments: Barrerite, an extremely rare zeolite was found in large cavities on a tidal flat.
Location: Rocky Pass, Kuiu Island, Alaska. Scale: 5.5 x 6 cm.
© Fabre Minerals

Barrerite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.7496:1:0.9803
Help on Cell Dimensions: Cell Dimensions: a = 13.643, b = 18.2, c = 17.842, Z = 2; V = 4,430.21 Den(Calc)= 2.01
Help on Crystal System: Crystal System: Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Amma or Ammm
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 4.054(1), 9.1(1), 3.028(0.8),

Physical Properties of Barrerite

Help on Cleavage: Cleavage: {???} Perfect
Help on Color: Color: White, Pink.
Help on Density: Density: 2.13
Help on Diaphaneity: Diaphaneity: Transparent to Translucent
Help on Hardness: Hardness: 3-4 - Calcite-Fluorite
Help on Luster: Luster: Vitreous (Glassy)
Help on Streak: Streak: white

Optical Properties of Barrerite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.048 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= -0.111 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.241,KPDmeas= 0.2274,KC= 0.217
Ncalc = 1.44 - 1.46
Help on Optical Data: Optical Data: Biaxial (-), a=1.4791, b=1.4851, g=1.4891, bire=0.0100, 2V(Calc)=78, 2V(Meas)=78.

Calculated Properties of Barrerite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.16 gm/cc
note: Specific Gravity of Barrerite =2.13 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.01
Boson Index = 0.99
Help on Photoelectric: Photoelectric: PEBarrerite = 1.61 barns/electron
U=PEBarrerite x relectron= 3.47 barns/cc.
Help on Radioactivity: Radioactivity:

GRapi = 22.57 (Gamma Ray American Petroleum Institute Units)
Concentration of Barrerite per GRapi unit = 4.43 (%)

Estimated Radioactivity from Barrerite - barely detectable


Barrerite Classification

Help on  Dana Class: Dana Class: (77)Tectosilicate Zeolite group
  (77.01)true zeolites
  (77.01.04)Heulandite and related species Heulandite-Ca (Ca,Na)2-3Al3(Al,Si)2Si13O36•12(H2O) C 2/m, Cm, C 2 Mono Heulandite-Na! (Na,Ca)2-3Al3(Al,Si)2Si13O36•12(H2O) C 2/m, Cm, C 2 Mono Heulandite-K! (K,Na,Ca)2-3Al3(Al,Si)2Si13O36•12(H2O) C 2/m, Cm, C 2 2/m Heulandite-Sr! (Sr,Na,Ca)2-3Al3(Al,Si)2Si13O36•12(H2O) C 2/m, Cm, C 2 Mono Heulandite-Ba! (Ba,Ca,K,Na,Sr)5Al9Si27O72•22(H2O) C 2/m 2/m Clinoptilolite-K (Na,K,Ca)2-3Al3(Al,Si)2Si13O36•12(H2O) C 2/m, C 2, Cm Mono Clinoptilolite-Na! (Na,K,Ca)2-3Al3(Al,Si)2Si13O36•12(H2O) C 2/m, C 2, Cm Mono Clinoptilolite-Ca! (Ca,Na,K)2-3Al3(Al,Si)2Si13O36•12(H2O) C 2/m 2/m Stilbite-Ca NaCa4[Al8Si28O72]•n(H2O)(n=28-32) C 2/m 2/m Stilbite-Na! Na3Ca3[Al8Si28O72]•n(H2O)(n=28-32) C 2/m 2/m Stellerite CaAl2Si7O18•7(H2O) F mmm 2/m 2/m 2/m Barrerite (Na,K,Ca)2Al2Si7O18•6(H2O) Amma or Ammm 2/m 2/m 2/m
Help on  Strunz Class: Strunz Class: 09.GE.15 09 - SILICATES (Germanates)
  09.G - Tektosilicates with Zeolitic H2O
  09.GE -Chains of T10O20 Tetrahedra
09.GE.15 Barrerite (Na,K,Ca)2Al2Si7O18•6(H2O) Amma or Ammm 2/m 2/m 2/m
09.GE.15 Stellerite CaAl2Si7O18•7(H2O) F mmm 2/m 2/m 2/m

Other Barrerite Information

Help on References: References: NAME( AntBidBlaNic2) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)
Help on See Also: See Also: Links to other databases for Barrerite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info

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Dana No: Strunz No: 09.GE.15





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