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Laumontite Mineral Data

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General Laumontite Information

Help on Chemical  Formula: Chemical Formula: CaAl2Si4O12•4(H2O)
Help on Composition: Composition: Molecular Weight = 470.44 gm
   Calcium    8.52 %  Ca   11.92 % CaO
   Aluminum  11.47 %  Al   21.67 % Al2O3
   Silicon   23.88 %  Si   51.09 % SiO2
   Hydrogen   1.71 %  H    15.32 % H2O
   Oxygen    54.42 %  O
            ______        ______ 
            100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: CaAl2Si4O12•4(H2O)
Help on Environment: Environment: Secondary mineral in basalts and andesites. Also occurs in metamorphic rocks and granites. Found in copper veins.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1801
Help on Locality: Locality: Nagy-Ag, Transylvania of Romania. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named after the Frenchman, F. P. N. de Laumont (1747-1834).
Help on Name Pronunciation: Name Pronunciation: Laumontite + Pronunciation Say LAUMONTITE
Help on Synonym: Synonym: Aedelforsite
  ICSD 72914
  PDF 45-1325

Laumontite Image

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Comments: Diamond-shaped prism of laumontite with chrysocolla.
Location: Azurite mine, Pinal County, Arizona, USA. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

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Comments: White, well developed laumontite crystals up to 1 cm. on matrix.
Location: Osilo, Sardegna, Italy. Scale: Specimen size 6 x 4.5 cm.
© Sandro Maggia/Minernet.it

Laumontite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =1.1313:1:0.5732
Help on Cell Dimensions: Cell Dimensions: a = 14.9, b = 13.17, c = 7.55, Z = 4; beta = 111.5° V = 1,378.47 Den(Calc)= 2.27
Help on Crystal System: Crystal System: Monoclinic - Prismatic H-M Symbol (2/m) Space Group: C 2/m
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 9.49(1), 4.156(0.6), 6.86(0.35),

Physical Properties of Laumontite

Help on Cleavage: Cleavage: {010} Perfect, {110} Perfect
Help on Color: Color: Brownish, Gray, Yellowish, Pearl white, Pink.
Help on Density: Density: 2.25 - 2.35, Average = 2.29
Help on Diaphaneity: Diaphaneity: Transparent to translucent to opaque
Help on Fracture: Fracture: Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.
Help on Habit: Habit: Bladed - Aggregates of thin lath-like crystals (e.g. kyanite).
Help on Habit: Habit: Crystalline - Fine - Occurs as well-formed fine sized crystals.
Help on Habit: Habit: Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Help on Hardness: Hardness: 3.5-4 - Copper Penny-Fluorite
Help on Luminescence: Luminescence: Fluorescent, Short UV=Weak white, Long UV=weak white.
Help on Luster: Luster: Vitreous (Glassy)
Help on Streak: Streak: white

Optical Properties of Laumontite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= 0.017 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.004 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2274,KPDmeas= 0.2244,KC= 0.2282
Ncalc = 1.51 - 1.54
Help on Optical Data: Optical Data: Biaxial (-), a=1.502-1.519, b=1.512-1.525, g=1.513-1.526, bire=0.0070-0.0110, 2V(Calc)=34-44, 2V(Meas)=25-47. Dispersion marked to extreme, r < v.
Help on Pleochroism (x): Pleochroism (x): colorless.
Help on Pleochroism (y): Pleochroism (y): colorless.

Calculated Properties of Laumontite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.30 gm/cc
note: Specific Gravity of Laumontite =2.27 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.01
Boson Index = 0.99
Help on Photoelectric: Photoelectric: PELaumontite = 2.32 barns/electron
U=PELaumontite x rElectron Density= 5.33 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Laumontite is Not Radioactive

Laumontite Classification

Help on  Dana Class: Dana Class: (77)Tectosilicate Zeolite group
  (77.01)true zeolites
  (77.01.01)Analcime and related species Analcime NaAlSi2O6•(H2O) P1 1 Pollucite (Cs,Na)2Al2Si4O12•(H2O) I a3d 4/m 3 2/m Wairakite CaAl2Si4O12•2(H2O) I2/a 2/m Laumontite CaAl2Si4O12•4(H2O) C 2/m 2/m Hsianghualite Ca3Li2Be3(SiO4)3F2 I 213 2 3
Help on  Strunz Class: Strunz Class: 09.GB.10 09 - SILICATES (Germanates)
  09.G - Tektosilicates with Zeolitic H2O
  09.GB -Chains of single connected 4-membered rings
09.GB.10 Laumontite CaAl2Si4O12•4(H2O) C 2/m 2/m

Other Laumontite Information

Help on See Also: See Also: Links to other databases for Laumontite :
1 - Am. Min. Crystal Structure Database
2 - Amethyst Galleries' Mineral Gallery
3 - Athena
4 - EUROmin Project
5 - Ecole des Mines de Paris
6 - Franklin Minerals(Dunn)
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 - Philatelic Mineralogy
16 - QUT Mineral Atlas
17 - Ruff.Info
19 - Zeolite Database by Bruno Herreros

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Dana No: Strunz No: 09.GB.10





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