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Montesommaite Mineral Data

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General Montesommaite Information

Help on Chemical  Formula: Chemical Formula: (K,Na)9Al9Si23O64•10(H2O)
Help on Composition: Composition: Molecular Weight = 2,433.32 gm
   Potassium  13.82 %  K    16.65 % K2O
   Sodium      0.19 %  Na    0.25 % Na2O
   Aluminum   10.42 %  Al   19.69 % Al2O3
   Silicon    26.09 %  Si   55.80 % SiO2
   Hydrogen    0.83 %  H     7.40 % H2O
   Oxygen     48.66 %  O
             ______        ______ 
             100.00 %       99.80 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: K8.6Na0.2Al9.4Si22.6O64•10(H2O)
Help on Environment: Environment: In volcanic ejecta.
Help on IMA Status: IMA Status: Approved IMA 1990
Help on Locality: Locality: Monte Somma, Pollena, Camania, Italy. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for the locality.
Help on Name Pronunciation: Name Pronunciation: Montesommaite + Pronunciation Say MONTESOMMAITE
Help on Synonym: Synonym: ICSD 40111(subcell)
  PDF 46-1351

Montesommaite Image

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Comments: Translucent prismatic montesommaite crystals in vugs.
Location: Pollena Quarry, Vesuvius, Naples, Campania, Italy. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Montesommaite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =1:1:1.7137
Help on Cell Dimensions: Cell Dimensions: a = 10.099, b = 10.099, c = 17.307, Z = 1; V = 1,765.14 Den(Calc)= 2.29
Help on Crystal System: Crystal System: Orthorhombic - Pyramidal H-M Symbol (mm2) Space Group: F dd2
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 3.13(1), 3.299(1), 6.589(0.75),

Physical Properties of Montesommaite

Help on Cleavage: Cleavage: None
Help on Color: Color: Colorless.
Help on Density: Density: 2.34
Help on Diaphaneity: Diaphaneity: Transparent
Help on Habit: Habit: Pyramidal - Crystals are shaped like pyramids.
Help on Luster: Luster: Vitreous (Glassy)
Help on Streak: Streak: white

Optical Properties of Montesommaite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.001 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= -0.022 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2199,KPDmeas= 0.2152,KC= 0.2151
Ncalc = 1.49 - 1.5
Help on Optical Data: Optical Data: Biaxial (-), a=1.498, b=1.506, g=1.507, bire=0.0090, 2V(Calc)=38, 2V(Meas)=35.

Calculated Properties of Montesommaite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.34 gm/cc
note: Specific Gravity of Montesommaite =2.34 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.01
Boson Index = 0.99
Help on Photoelectric: Photoelectric: PEMontesommaite = 2.69 barns/electron
U=PEMontesommaite x relectron= 6.30 barns/cc.
Help on Radioactivity: Radioactivity:

GRapi = 199.31 (Gamma Ray American Petroleum Institute Units)
Concentration of Montesommaite per GRapi unit = 0.50 (%)

Estimated Radioactivity from Montesommaite - barely detectable


Montesommaite Classification

Help on  Dana Class: Dana Class: (77)Tectosilicate Zeolite group
  (77.01)true zeolites
  (77.01.03)Gismondine and related species Gismondine Ca2Al4Si4O16•9(H2O) P 21/c 2/m Amicite K2Na2Al4Si4O16•5(H2O) I2 2 Garronite Na2Ca5Al12Si20O64•27(H2O) I 41/a 4/m Gobbinsite (Na2,Ca)2K2Al6Si10O32•12(H2O) P mn21 mm2 Harmotome (Ba,Na,K)1-2(Si,Al)8O16•6(H2O) P 21/m 2/m Phillipsite-Na (Na,K,Ca)1-2(Si,Al)8O16•6(H2O) P 21/m 2/m Phillipsite-Ca! (Ca,K,Na)1-2(Si,Al)8O16•6(H2O) P 21/m 2/m Phillipsite-K! (K,Na,Ca)1-2(Si,Al)8O16•6(H2O) P 21/m 2/m Perlialite K8Tl4Al12Si24O72•20(H2O) P 6/mmm 6/m 2/m 2/m Paulingite-K (K2,Ca,Na2,Ba)5Al10Si35O90•45(H2O) Im3m 4/m 3 2/m Paulingite-Na! (Na2,K2,Ca,Ba)5Al10Si35O90•45(H2O) Im3m 4/m 3 2/m Paulingite-Ca! (Ca,K,Na,Ba)5[Al10Si35O84]•34(H2O) Im3m 4/m 3 2/m Mazzite-Mg K2CaMg2(Al,Si)36O72•28(H2O) P 63/mmc 6/m 2/m 2/m Mazzite-Na! Na8Al8Si28O72•30H2O P 63/mmc 6/m 2/m 2/m Merlinoite (K,Ca,Na,Ba)7Si23Al9O64•23(H2O) I mmm 2/m 2/m 2/m Montesommaite (K,Na)9Al9Si23O64•10(H2O) F dd2 mm2
Help on  Strunz Class: Strunz Class: 09.GB.30 09 - SILICATES (Germanates)
  09.G - Tektosilicates with Zeolitic H2O
  09.GB -Chains of single connected 4-membered rings
09.GB.30 Montesommaite (K,Na)9Al9Si23O64•10(H2O) F dd2 mm2

Other Montesommaite Information

Help on References: References: NAME( AntBidBlaNic2) PHYS. PROP.(Am.Min.,Vol.75,p1415-1420,1990) OPTIC PROP.(Am.Min.,Vol.75,p1415-1420,1990)
Help on See Also: See Also: Links to other databases for Montesommaite :
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
16 - Zeolite Database by Bruno Herreros

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Dana No: Strunz No: 09.GB.30





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