Cookeite Mineral Data

Cookeite Mineral Data

[Thumbnails] [Miniatures] [Cabinets] [About Us] [FAQ]
Welcome To Mason's Minerals
Your Source for Beautiful Minerals and Crystals
We offer a no-questioned-asked Satisfaction Guarantee

General Cookeite Information

Chemical Formula:

LiAl4(Si3Al)O10(OH)8

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

Empirical Formula:

LiAl₅Si₃O₁₀(OH)₈

Environment:

Alteration of lithia tourmalines and lepidolite in pegmatites.

IMA Status:

Valid Species (Pre-IMA) 1866

Locality:

Oxford Co., Maine, USA. Pala, San Diego Co., California, USA. Link to MinDat.org Location Data.

Cookeite Image

Images:

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

Axial Ratios:

a:b:c =0.5744:1:3.2138

Cell Dimensions:

a = 5.13, b = 8.93, c = 28.7, Z = 4; beta = 98.75° V = 1,299.47 Den(Calc)= 2.67

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: P 2₁/a

$Help on X Ray Diffraction:$ X Ray Diffraction:

By Intensity(I/I_o): 2.315(1), 3.52(0.9), 4.7(0.9),

Crystal Structure:

Mouse
drag1 - LMB Manipulate Structure
drag2 - RMB Resize/Rotate
Keyboard
S - Stereo Pair on/off
H - Help Screen
I - Data Info
A - Atoms On/Off
P - Polyhedra On/Off
B - Bonds On/Off
Help on Above

Zheng H , Bailey S W , American Mineralogist , 82 (1997) p.1007-1013, Refinement of the cookeite r structure

Physical Properties of Cookeite

Cleavage:

[001] Perfect

Color:

White, Green, Brown, Yellowish white, Pinkish white.

Density:

2.67

Diaphaniety:

Transparent to translucent

Fracture:

Flexible - Flexible fragments.

Habit:

Micaceous - Platy texture with "flexible" plates.

Habit:

Pseudo Hexagonal - Crystals show a hexagonal outline.

Hardness:

2.5 - Finger Nail

Luminescence:

Non-fluorescent.

Luster:

Vitreous (Glassy)

Streak:

white

Optical Properties of Cookeite

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

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

Electron Density:

r_electron=2.68 gm/cc
note: r_Cookeite=2.67 gm/cc.

Fermion Index

Fermion Index = 0.00879
Boson Index = 0.99121

Photoelectric:

PE_Cookeite= 1.42 barns/electron
U=PE_Cookeite x r_electron= 3.79 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)

Cookeite is Not Radioactive

Cookeite Classification

Dana Class:

71.4.1.2 (71)Phyllosilicate Sheets of Six-Membered Rings

(71.4)interlayered 1:1, 2:1, and octahedra

(71.4.1)Chlorite group (Tri-Dioctahedral)

71.4.1.1 Donbassite Al2[Al2.33][Si3AlO10](OH)8 C 2/m 2/m

71.4.1.2 Cookeite LiAl4(Si3Al)O10(OH)8 P 2₁/a 2/m

71.4.1.3 Sudoite Mg2(Al,Fe)3Si3AlO10(OH)8 C 2/m 2/m

71.4.1.4 Clinochlore (Mg,Fe)5Al(Si3Al)O10(OH)8 C 2/m 2/m

71.4.1.5 Nimite (Ni,Mg,Fe)5Al(Si3Al)O10(OH)8 C 2/m 2/m

71.4.1.6 Baileychlore (Zn,Al,[])3[Fe2Al][Si3AlO10](OH)8 C1,C1 Tri

71.4.1.7 Chamosite (Fe,Mg,Fe)5Al(Si3Al)O10(OH,O)8 C 2/m 2/m

71.4.1.8 Pennantite Mn5Al(Si3Al)O10(OH)8 C 2/m 2/m

71.4.1.9 Orthochamosite! (Fe,Mg,Fe)5Al(Si3Al)O10(OH,O)8 C3m-pseudoHEX Ortho

71.4.1.10 Borocookeite! Li(13x)Al(4-x)(BSi3)O10(OH,F)8[x=0-0.33] pseudo C 2/m 2/m

Strunz Class:

VIII/H.23-90 VIII - Silicates

VIII/H - Phyllosilicates (layered) Mica like with [Si4O10]4- and related groups

VIII/H.23 - Chlorite group

VIII/H.23-10 Sudoite Mg2(Al,Fe)3Si3AlO10(OH)8 C 2/m 2/m

VIII/H.23-20 Clinochlore (Mg,Fe)5Al(Si3Al)O10(OH)8 C 2/m 2/m

VIII/H.23-30 Chamosite (Fe,Mg,Fe)5Al(Si3Al)O10(OH,O)8 C 2/m 2/m

VIII/H.23-40 Orthochamosite (Fe,Mg,Fe)5Al(Si3Al)O10(OH,O)8 C3m-pseudoHEX Ortho

VIII/H.23-50 Baileychlore (Zn,Al,[])3[Fe2Al][Si3AlO10](OH)8 C1,C1 Tri

VIII/H.23-60 Pennantite Mn5Al(Si3Al)O10(OH)8 C 2/m 2/m

VIII/H.23-70 Nimite (Ni,Mg,Fe)5Al(Si3Al)O10(OH)8 C 2/m 2/m

VIII/H.23-80 Gonyerite Mn3[Mn3Fe][(Si,Fe)4O10](OH,O)8 pseudo-HEX Ortho

VIII/H.23-90 Cookeite LiAl4(Si3Al)O10(OH)8 P 2₁/a 2/m

VIII/H.23-95 Borocookeite! Li(13x)Al(4-x)(BSi3)O10(OH,F)8[x=0-0.33] pseudo C 2/m 2/m

VIII/H.23-100 Manandonite Li2Al4[(Si2AlB)O10](OH)8 C1 1

VIII/H.23-110 Franklinfurnaceite Ca2(Fe,Al)MnMn3Zn2Si2O10(OH)8 C 2 2

Other Cookeite Information

References:

NAME( Ford32) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

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 - Google Images
6 - Google Scholar
7 - Handbook of Mineralogy (MinSocAm)
8 - Handbook of Mineralogy (UofA)
9 - MinDAT
10 - MinMax(Deutsch)
11 - MinMax(English)
12 - Mineralienatlas (Deutsch)
13 - QUT Mineral Atlas
14 - Ruff.Info
15 - Scandinavian mineral gallery
16 - WWW-MINCRYST

Search for Cookeite using:

[ALTAVISTA] [AOL] [All-The-Web] [HotBot] [Ixquick] [MAMMA] [MSN.COM] [Netscape] [Scirus] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Cookeite :

AA Mineral Specimens

B & L Fine Minerals

Dan Weinrich Fine Minerals

Dan Weinrich Auctions

John Betts Fine Minerals

Mason's Minerals

Mineral News

Mineral of the Month Club

MineralsWeb Fine Minerals

The GeoZone

Wrights Rock Shop

Translate Cookeite Mineral Data :

Ask about Cookeite here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in Español

Print or Cut-and-Paste your Cookeite Specimen Label here :

Cookeite

LiAl4(Si3Al)O10(OH)8
Dana No: 71.4.1.2 Strunz No: VIII/H.23-90
Locality:

Notes: