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Cookeite Mineral Data

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General Cookeite Information

Help on Chemical  Formula: Chemical Formula: LiAl4(Si3Al)O10(OH)8
Help on Composition: Composition: Molecular Weight = 522.16 gm
   Lithium    1.33 %  Li    2.86 % Li2O
   Aluminum  25.84 %  Al   48.82 % Al2O3
   Silicon   16.14 %  Si   34.52 % SiO2
   Hydrogen   1.54 %  H    13.80 % H2O
   Oxygen    55.15 %  O
            ______        ______ 
            100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: LiAl5Si3O10(OH)8
Help on Environment: Environment: Alteration of lithia tourmalines and lepidolite in pegmatites.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1866
Help on Locality: Locality: Oxford Co., Maine, USA. Pala, San Diego Co., California, USA. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Josiah B. Cooke, Jr. (1827-1894), American mineralogist and chemist, Harvard University, Cambridge, Massachusetts, USA.
 

Cookeite Image

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  Cookeite

Comments: Large tan-colored cookeite epimorph after a large 12 cm quartz crystal. The outer faces of the epimorph are overgrown with milky quartz crystals up to 15 mm long.
Location: Bennett & Orchard Pit mines, Buckfield, Oxford Co., Maine, USA. Scale: 17x17x11 cm.
© John Betts - Fine Minerals

Cookeite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.5744:1:3.2138
Help on Cell Dimensions: Cell Dimensions: a = 5.13, b = 8.93, c = 28.7, Z = 4; beta = 98.75° V = 1,299.47 Den(Calc)= 2.67
Help on Crystal System: Crystal System: Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 21/a
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.315(1), 3.52(0.9), 4.7(0.9),
 

Physical Properties of Cookeite

Help on Cleavage: Cleavage: {001} Perfect
Help on Color: Color: White, Green, Brown, Yellowish white, Pinkish white.
Help on Density: Density: 2.67
Help on Diaphaneity: Diaphaneity: Transparent to translucent
Help on Fracture: Fracture: Flexible - Flexible fragments.
Help on Habit: Habit: Micaceous - Platy texture with "flexible" plates.
Help on Habit: Habit: Pseudo Hexagonal - Crystals show a hexagonal outline.
Help on Hardness: Hardness: 2.5 - Finger Nail
Help on Luminescence: Luminescence: Non-fluorescent.
Help on Luster: Luster: Vitreous (Glassy)
Help on Streak: Streak: white
 

Optical Properties of Cookeite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= 0.044 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= 0.044 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2185,KPDmeas= 0.2185,KC= 0.2286
Ncalc = 1.61
Help on Optical Data: Optical Data: Biaxial (+), a=1.572-1.576, b=1.579-1.584, g=1.589-1.6, bire=0.0170-0.0240
 

Calculated Properties of Cookeite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.68 gm/cc
note: Specific Gravity of Cookeite =2.67 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0087996327
Boson Index = 0.9912003673
Help on Photoelectric: Photoelectric: PECookeite = 1.42 barns/electron
U=PECookeite x rElectron Density= 3.79 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Cookeite is Not Radioactive
 

Cookeite Classification

Help on  Dana Class: Dana Class: 71.04.01.02 (71)Phyllosilicate Sheets of Six-Membered Rings
  (71.04)interlayered 1:1, 2:1, and octahedra
  (71.04.01)Chlorite group (Tri-Dioctahedral)
 
71.04.01.01 Donbassite Al2[Al2.33][Si3AlO10](OH)8 C 2/m 2/m
 
71.04.01.02 Cookeite LiAl4(Si3Al)O10(OH)8 P 21/a 2/m
 
71.04.01.03 Sudoite Mg2(Al,Fe)3Si3AlO10(OH)8 C 2/m 2/m
 
71.04.01.04 Clinochlore (Mg,Fe)5Al(Si3Al)O10(OH)8 C 2/m 2/m
 
71.04.01.05 Nimite (Ni,Mg,Fe)5Al(Si3Al)O10(OH)8 C 2/m 2/m
 
71.04.01.06 Baileychlore (Zn,Al,[])3[Fe2Al][Si3AlO10](OH)8 C1,C1 Tri
 
71.04.01.07 Chamosite (Fe,Mg,Fe)5Al(Si3Al)O10(OH,O)8 C 2/m 2/m
 
71.04.01.08 Pennantite Mn5Al(Si3Al)O10(OH)8 C 2/m 2/m
 
71.04.01.09 Orthochamosite! (Fe,Mg,Fe)5Al(Si3Al)O10(OH,O)8 C3m-pseudoHEX Ortho
 
71.04.01.10 Borocookeite! Li(13x)Al(4-x)(BSi3)O10(OH,F)8[x=0-0.33] pseudo C 2/m 2/m
Help on  Strunz Class: Strunz Class: 09.EC.55 09 - SILICATES (Germanates)
  09.E - Phyllosilicates
  09.EC -Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets
 
09.EC.55 Donbassite Al2[Al2.33][Si3AlO10](OH)8 C 2/m 2/m
 
09.EC.55 Baileychlore (Zn,Al,[])3[Fe2Al][Si3AlO10](OH)8 C1,C1 Tri
 
09.EC.55 Clinochlore (Mg,Fe)5Al(Si3Al)O10(OH)8 C 2/m 2/m
 
09.EC.55 Cookeite LiAl4(Si3Al)O10(OH)8 P 21/a 2/m
 
09.EC.55 Chamosite (Fe,Mg,Fe)5Al(Si3Al)O10(OH,O)8 C 2/m 2/m
 
09.EC.55 Franklinfurnaceite Ca2(Fe,Al)MnMn3Zn2Si2O10(OH)8 C 2 2
 
09.EC.55 Nimite (Ni,Mg,Fe)5Al(Si3Al)O10(OH)8 C 2/m 2/m
 
09.EC.55 Gonyerite Mn3[Mn3Fe][(Si,Fe)4O10](OH,O)8 pseudo-HEX Ortho
 
09.EC.55 Odinite (Fe,Mg,Al,Fe,Ti,Mn)2.5(Si,Al)2O5(OH)4 Cm m
 
09.EC.55 Orthochamosite (Fe,Mg,Fe)5Al(Si3Al)O10(OH,O)8 C3m-pseudoHEX Ortho
 
09.EC.55 Pennantite Mn5Al(Si3Al)O10(OH)8 C 2/m 2/m
 
09.EC.55 Sudoite Mg2(Al,Fe)3Si3AlO10(OH)8 C 2/m 2/m
 
09.EC.55 Glagolevite! NaMg6[Si3AlO10](OH,O)8•H2O C1 1
 
09.EC.55 Borocookeite! Li(13x)Al(4-x)(BSi3)O10(OH,F)8[x=0-0.33] pseudo C 2/m 2/m
 

Other Cookeite Information

Help on References: References: NAME( Ford32) 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 Cookeite :
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 - Mineral and Gemstone Kingdom
12 - Mineralienatlas (Deutsch)
13 - Online Mineral Museum
14 - QUT Mineral Atlas
15 - Ruff.Info
16 - Scandinavian mineral gallery
17 - WWW-MINCRYST

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Cookeite

LiAl4(Si3Al)O10(OH)8
Dana No: 71.04.01.02 Strunz No: 09.EC.55
Locality:

 

Notes:

 

 
   
 


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