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Glauconite Mineral Data

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General Glauconite Information

Help on Chemical  Formula: Chemical Formula: (K,Na)(Fe+++,Al,Mg)2(Si,Al)4O10(OH)2
Help on Composition: Composition: Molecular Weight = 426.93 gm
   Potassium   5.49 %  K     6.62 % K2O
   Sodium      0.27 %  Na    0.36 % Na2O
   Magnesium   2.28 %  Mg    3.78 % MgO
   Aluminum    1.90 %  Al    3.58 % Al2O3
   Iron       19.62 %  Fe    3.37 % FeO / 24.31 % Fe2O3
   Silicon    25.00 %  Si   53.48 % SiO2
   Hydrogen    0.47 %  H     4.22 % H2O
   Oxygen     44.97 %  O
             ______        ______ 
             100.00 %       99.72 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: K0.6Na0.05Fe3+1.3Mg0.4Fe2+0.2Al0.3Si3.8O10(OH)2
Help on Environment: Environment: Altered from detrital biotite by marine diagenesis in shallow water under reducing conditions; especially in sandstone.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1828
Help on Locality: Locality: Otago Peninsula, New Zealand. Common world wide. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: From the Greek "glaucos" for the blue green color.
Help on Name Pronunciation: Name Pronunciation: Glauconite + Pronunciation Say GLAUCONITE

Glauconite Image

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Comments: Green glauconite intermixed with quartz.
Location: Ightham, Kent, England. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Glauconite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.5773:1:1.1206
Help on Cell Dimensions: Cell Dimensions: a = 5.234, b = 9.066, c = 10.16, Z = 2; beta = 100.5° V = 474.03 Den(Calc)= 2.99
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): 10.1(1), 2.59(1), 4.53(0.8),1.511(0.6), 2.396(0.6), 3.33(0.6), 3.63(0.4),

Physical Properties of Glauconite

Help on Cleavage: Cleavage: {001} Perfect
Help on Color: Color: Blue green, Green, Yellow green.
Help on Density: Density: 2.4 - 2.95, Average = 2.67
Help on Diaphaneity: Diaphaneity: Translucent to Subopaque
Help on Habit: Habit: Micaceous - Platy texture with "flexible" plates.
Help on Hardness: Hardness: 2 - Gypsum
Help on Luminescence: Luminescence: Non-fluorescent.
Help on Luster: Luster: Earthy (Dull)
Help on Magnetism: Magnetism: Nonmagnetic
Help on Streak: Streak: light green

Optical Properties of Glauconite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= 0.026 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.128 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2067,KPDmeas= 0.231,KC= 0.2371
Ncalc = 1.57 - 1.71
Help on Optical Data: Optical Data: Biaxial (-), a=1.59-1.612, b=1.609-1.643, g=1.61-1.644, bire=0.0200-0.0320, 2V(Calc)=20-24, 2V(Meas)=0-20. Dispersion r > v.
Help on Pleochroism (x): Pleochroism (x): lemon yellow, pale yellowish green, or bright green.
Help on Pleochroism (y): Pleochroism (y): green, dark green, yellowish green, bluish green, or olive green.
Help on Pleochroism (z): Pleochroism (z): green, dark green, yellowish green, bluish green, or olive green.

Calculated Properties of Glauconite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.64 gm/cc
note: Specific Gravity of Glauconite =2.68 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.01
Boson Index = 0.99
Help on Photoelectric: Photoelectric: PEGlauconite = 7.42 barns/electron
U=PEGlauconite x relectron= 19.61 barns/cc.
Help on Radioactivity: Radioactivity:

GRapi = 78.31 (Gamma Ray American Petroleum Institute Units)
Concentration of Glauconite per GRapi unit = 1.28 (%)

Estimated Radioactivity from Glauconite - barely detectable


Glauconite Classification

Help on  Dana Class: Dana Class: 71.02.02a.05 (71)Phyllosilicate Sheets of Six-Membered Rings
  (71.02)with 2:1 Layers
  (71.02.02a)Mica Group (Muscovite subgroup)
71.02.02a.01 Muscovite KAl2(Si3Al)O10(OH,F)2 C 2/m 2/m
71.02.02a.02 Paragonite NaAl2(Si3Al)O10(OH)2 C 2/c,Cc Mono
71.02.02a.03 Chernykhite (Ba,Na)V,Al)2(Si,Al)4O10(OH)2 C 2/c 2/m
71.02.02a.04 Roscoelite K(V,Al,Mg)2AlSi3O10(OH)2 C 2/m 2/m
71.02.02a.05 Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2 C 2/m 2/m
71.02.02a.06 Celadonite K(Mg,Fe)(Fe,Al)[Si4O10](OH)2 C 2/m 2/m
71.02.02a.06b Ferroceladonite! K2FeFeSi8O20(OH)4 C 2/m 2/m
71.02.02a.06c Ferroaluminoceladonite! K2Fe2Al2Si8O20(OH)4 C 2/m 2/m
71.02.02a.06d Aluminoceladonite! KAl(Mg,Fe)[]Si4O10(OH)2 2/m
71.02.02a.06e Chromceladonite! KCrMg(Si4O10)(OH)2 C 2 2
71.02.02a.07 Tobelite (NH4,K)Al2(Si3Al)O10(OH)2 C 2/m 2/m
71.02.02a.08 Nanpingite Cs(Al,Mg,Fe,Li)2(Si3Al)O10(OH,F)2 C 2/c 2/m
71.02.02a.09 Boromuscovite KAl2(Si3B)O10(OH,F)2 C 2/m 2/m
71.02.02a.10 Montdorite (K,Na)(Fe,Mn,Mg)2.5[Si4O10](F,OH)2 C 2/c 2/m
71.02.02a.11 Chromphyllite! (K,Ba)(Cr,Al)2[AlSi3O10](OH,F)2 C 2c 2/m
71.02.02a.12 Shirokshinite! K(NaMg2)Si4O10F2 C 2/m 2/m
Help on  Strunz Class: Strunz Class: 09.EC.15 09 - SILICATES (Germanates)
  09.E - Phyllosilicates
  09.EC -Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets
09.EC.15 Boromuscovite KAl2(Si3B)O10(OH,F)2 C 2/m 2/m
09.EC.15 Celadonite K(Mg,Fe)(Fe,Al)[Si4O10](OH)2 C 2/m 2/m
09.EC.15 Chernykhite (Ba,Na)V,Al)2(Si,Al)4O10(OH)2 C 2/c 2/m
09.EC.15 Chromphyllite! (K,Ba)(Cr,Al)2[AlSi3O10](OH,F)2 C 2c 2/m
09.EC.15 Glauconite (K,Na)(Fe,Al,Mg)2(Si,Al)4O10(OH)2 C 2/m 2/m
09.EC.15 Aluminoceladonite! KAl(Mg,Fe)[]Si4O10(OH)2 2/m
09.EC.15 Ferroaluminoceladonite! K2Fe2Al2Si8O20(OH)4 C 2/m 2/m
09.EC.15 Ferroceladonite! K2FeFeSi8O20(OH)4 C 2/m 2/m
09.EC.15 Montdorite (K,Na)(Fe,Mn,Mg)2.5[Si4O10](F,OH)2 C 2/c 2/m
09.EC.15 Nanpingite Cs(Al,Mg,Fe,Li)2(Si3Al)O10(OH,F)2 C 2/c 2/m
09.EC.15 Tobelite (NH4,K)Al2(Si3Al)O10(OH)2 C 2/m 2/m
09.EC.15 Roscoelite K(V,Al,Mg)2AlSi3O10(OH)2 C 2/m 2/m
09.EC.15 Muscovite KAl2(Si3Al)O10(OH,F)2 C 2/m 2/m
09.EC.15 Paragonite NaAl2(Si3Al)O10(OH)2 C 2/c,Cc Mono
09.EC.15 Tainiolite KLiMg2Si4O10F2 C 2/m 2/m
09.EC.15 Chromceladonite! KCrMg(Si4O10)(OH)2 C 2 2
09.EC.15 Ganterite! [Ba0.5(Na,K)0.5]Al2(Si2.5Al1.5O10)(OH)2 C 2/c 2/m

Other Glauconite Information

Help on References: References: NAME( AntBidBlaNic2) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Heinrich65)
Help on See Also: See Also: Links to other databases for Glauconite :
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 - Minerals in Thin Sections-Humboldt State
13 - Online Mineral Museum
14 - QUT Mineral Atlas
15 - Ruff.Info

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Dana No: 71.02.02a.05 Strunz No: 09.EC.15





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