Phlogopite Mineral Data

General Phlogopite Information

Chemical Formula:

KMg3(Si3Al)O10(F,OH)2

Composition:

Molecular Weight = 419.25 gm

Potassium 9.33 % K 11.23 % K₂O

Magnesium 17.39 % Mg 28.84 % MgO

Aluminum 6.44 % Al 12.16 % Al₂O₃

Silicon 20.10 % Si 42.99 % SiO₂

Hydrogen 0.24 % H 2.15 % H₂O

Oxygen 41.98 % O

Fluorine 4.53 % F 4.53 % F

- % F -1.91 % -O=F₂

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

KMg₃AlSi₃O₁₀F(OH)

Environment:

Contact and regional metamorphic limestones and dolomites. Ultramafic igneous rocks.

IMA Status:

Valid Species (Pre-IMA) 1841

Locality:

St. Lawrence Co., at Edwards, New York, USA. Link to MinDat.org Location Data.

Name Origin:

From the Greek flogopos - "resembling fire."

Name Pronunciation:

Phlogopite + Pronunciation

Synonym:

Magnesium Mica

Phlogopite Image

Images:

Phlogopite

Comments: Exceptionally well-crystallized wine-colored pseudo-hexagonal crystal of phlogopite on white calcite.
Location: Kalu Khan, Badakhshan, Afghanistan. Scale: 6 x 5.5 cm.
© Fabre Minerals

Images:

Phlogopite Serendibite

Comments: Blue serendibite, with golden colored phlogopite, in white marble.
Location: Near Johnsberg, Warren County, New York, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Images:

Phlogopite Lazurite

Comments: Gemmy brownish phlogopite crystals on blue lazurite (lapis) matrix with minor pyrite.
Location: Koksha Valley, Badakhshan Province, Afghanistan. Scale: 10 x 11.5 cm.
© Kevin Ward

Phlogopite Crystallography

Axial Ratios:

a:b:c =0.5752:1:2.2058

Cell Dimensions:

a = 5.31, b = 9.23, c = 20.36, Z = 4; beta = 99.3° V = 984.75 Den(Calc)= 2.83

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: C 2/m

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

By Intensity(I/I_o): 9.998(1), 2.613(0.53), 3.382(0.33),

Forms:

Mouse
Dbl Clk - Start-Stop Rotation
RMB - Cycle Display Modes
Drag1 - Manipulate Crystal
Drag2 - Resize
Keyboard
S - Stereo
I - Indicies
<space> - Start-Stop Rotation
F - Fit to Screen
M - Menu
Help on Above

Forms: ( 1 1 2) ( 2 2 1) ( 0 1 0) ( 0 0 1)

Warning: this large pop-up is very compute intensive and may not work well with some computers.

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

Hendricks S B , Jefferson M E , American Mineralogist , 24 (1939) p.729-771, Polymorphism of the micas with optical measurements

View Additional jPOWD Structure files for Phlogopite
[1] [10] [11] [12] [13] [14] [15] [16] [17] [18] [19] [2] [20] [21] [22] [23] [24] [25] [26] [27] [28] [29] [3] [30] [31] [32] [33] [34] [35] [36] [37] [38] [39] [4] [40] [41] [42] [43] [44] [45] [46] [47] [48] [49] [5] [50] [51] [52] [53] [54] [55] [56] [57] [58] [59] [6] [60] [61] [62] [63] [64] [65] [66] [67] [68] [69] [7] [70] [71] [72] [8] [9]

Physical Properties of Phlogopite

Cleavage:

{001} Perfect

Color:

Brown, Gray, Green, Yellow, Reddish brown.

Density:

2.7 - 2.9, Average = 2.8

Diaphaneity:

Transparent to translucent

Fracture:

Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.

Habit:

Lamellar - Thin laminae producing a lamellar structure.

Habit:

Micaceous - Platy texture with "flexible" plates.

Habit:

Scaly - Morphology like fish scales.

Hardness:

2-2.5 - Gypsum-Finger Nail

Luminescence:

Fluorescent, Short UV=Straw to Lemon Yellow, Long UV=Weak Blue-white to blue-gray.

Luster:

Vitreous - Pearly

Streak:

white

Optical Properties of Phlogopite

Gladstone-Dale:

CI meas= -0.009 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.002 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2034,KPDmeas= 0.2055,KC= 0.2037
Ncalc = 1.55 - 1.59

Optical Data:

Biaxial (-), a=1.53-1.573, b=1.557-1.617, g=1.558-1.618, bire=0.0280-0.0450, 2V(Calc)=16-20, 2V(Meas)=0-12. Dispersion weak to distinct, r < v.

Pleochroism (x):

colorless, pale yellow, orange, salmon pink, or brown. red brown.

Pleochroism (y):

brownish yellow, buff, reddish orange, pale reddish brown, or colorless.

Calculated Properties of Phlogopite

Electron Density:

Bulk Density (Electron Density)=2.81 gm/cc
note: Specific Gravity of Phlogopite =2.83 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Phlogopite= 2.30 barns/electron
U=PE_Phlogopite x r_electron= 6.46 barns/cc.

Radioactivity:

GRapi = 133.53 (Gamma Ray American Petroleum Institute Units)
Concentration of Phlogopite per GRapi unit = 0.75 (%)

Estimated Radioactivity from Phlogopite - barely detectable

Phlogopite Classification

Dana Class:

71.02.02b.01 (71)Phyllosilicate Sheets of Six-Membered Rings

(71.02)with 2:1 Layers

(71.02.02b)Mica Group (Biotite subgroup)

71.02.02b.01 Phlogopite KMg3(Si3Al)O10(F,OH)2 C 2/m 2/m

71.02.02b.01a Tetraferriphlogopite! KMg3FeSi3O10(OH)2 2/m

71.02.02b.01b Shirozulite! KMn3(AlSi3)O10(OH,F)2 C 2/m 2/m

71.02.02b.01c Fluorophlogopite! KMg3(AlSi3)O10F2 C 2/m 2/m

71.02.02b.02 Biotite* K(Mg,Fe)3[AlSi3O10(OH,F)2 C 2/m 2/m

71.02.02b.03 Annite KFe3AlSi3O10(OH,F)2 C 2/m 2/m

71.02.02b.03a Fluorannite! KFe3AlSi3O10F2 C 2/m 2/m

71.02.02b.04 Tetraferriannite K(Fe,Mg)3(Fe,Al)Si3O10(OH)2 C 2/m 2/m

71.02.02b.05 Siderophyllite KFe2Al(Al2Si2)O10(F,OH)2 C 2/m 2/m

71.02.02b.05a Eastonite! KMg2Al[Al2Si2O10](OH)2 2/m

71.02.02b.06 Hendricksite K(Zn,Mg,Mn)3Si3AlO10(OH)2 C 2/m 2/m

71.02.02b.07 Lepidolite K(Li,Al)3(Si,Al)4O10(F,OH)2 C 2/m,Cm Mono

71.02.02b.08 Polylithionite KLi2AlSi4O10(F,OH)2 C 2/m 2/m

71.02.02b.08a Trilithionite! KLi1.5Al1.5AlSi3O10F2 C 2/m 2/m

71.02.02b.08b Sokolovaite! CsLi2AlSi4O10F2 C 2/m, C 2 or Cm Mono

71.02.02b.09 Tainiolite KLiMg2Si4O10F2 C 2/m 2/m

71.02.02b.10 Zinnwaldite KLiFeAl(AlSi3)O10(F,OH)2 C 2/m 2/m

71.02.02b.11 Norrishite K(Mn2Li)Si4O10(O)2 C 2/m 2/m

71.02.02b.12 Masutomilite K(Li,Al,Mn)3[(Si,Al)4O10](F,OH)2 C 2/m 2/m

71.02.02b.13 Aspidolite NaMg3AlSi3O10(OH)2 C 2/m 2/m

71.02.02b.14 Wonesite (Na,K).5(Mg,Fe,Al)3(Si,Al)4O10(OH,F)2 C 2/m 2/m

71.02.02b.15 Preiswerkite NaMg2Al3Si2O10(OH)2 C 2/m 2/m

71.02.02b.16 Ephesite NaLiAl2(Al2Si2)O10(OH)2 C 2/c 2/m

71.02.02b.18 Suhailite! (NH4)Fe3(Si3Al)O10(OH)2 C 2/m? 2/m

Strunz Class:

09.EC.20 09 - SILICATES (Germanates)

09.E - Phyllosilicates

09.EC -Phyllosilicates with mica sheets, composed of tetrahedral and octahedral nets

09.EC.20 Annite KFe3AlSi3O10(OH,F)2 C 2/m 2/m

09.EC.20 Biotite* K(Mg,Fe)3[AlSi3O10(OH,F)2 C 2/m 2/m

09.EC.20 Hendricksite K(Zn,Mg,Mn)3Si3AlO10(OH)2 C 2/m 2/m

09.EC.20 Ephesite NaLiAl2(Al2Si2)O10(OH)2 C 2/c 2/m

09.EC.20 Aspidolite NaMg3AlSi3O10(OH)2 C 2/m 2/m

09.EC.20 Lepidolite K(Li,Al)3(Si,Al)4O10(F,OH)2 C 2/m,Cm Mono

09.EC.20 Preiswerkite NaMg2Al3Si2O10(OH)2 C 2/m 2/m

09.EC.20 Masutomilite K(Li,Al,Mn)3[(Si,Al)4O10](F,OH)2 C 2/m 2/m

09.EC.20 Wonesite (Na,K).5(Mg,Fe,Al)3(Si,Al)4O10(OH,F)2 C 2/m 2/m

09.EC.20 Polylithionite KLi2AlSi4O10(F,OH)2 C 2/m 2/m

09.EC.20 Phlogopite KMg3(Si3Al)O10(F,OH)2 C 2/m 2/m

09.EC.20 Norrishite K(Mn2Li)Si4O10(O)2 C 2/m 2/m

09.EC.20 Siderophyllite KFe2Al(Al2Si2)O10(F,OH)2 C 2/m 2/m

09.EC.20 Fluorannite! KFe3AlSi3O10F2 C 2/m 2/m

09.EC.20 Shirokshinite! K(NaMg2)Si4O10F2 C 2/m 2/m

09.EC.20 Zinnwaldite KLiFeAl(AlSi3)O10(F,OH)2 C 2/m 2/m

09.EC.20 Eastonite! KMg2Al[Al2Si2O10](OH)2 2/m

09.EC.20 Tetraferriannite K(Fe,Mg)3(Fe,Al)Si3O10(OH)2 C 2/m 2/m

09.EC.20 Tetraferriphlogopite! KMg3FeSi3O10(OH)2 2/m

09.EC.20 Trilithionite! KLi1.5Al1.5AlSi3O10F2 C 2/m 2/m

09.EC.20 Sokolovaite! CsLi2AlSi4O10F2 C 2/m, C 2 or Cm Mono

09.EC.20 Shirozulite! KMn3(AlSi3)O10(OH,F)2 C 2/m 2/m

09.EC.20 Suhailite! (NH4)Fe3(Si3Al)O10(OH)2 C 2/m? 2/m

09.EC.20 Fluorophlogopite! KMg3(AlSi3)O10F2 C 2/m 2/m

Other Phlogopite Information

Search for Phlogopite using:

[AOL] [Bing] [Dog Pile] [GeoScienceWorld] [HotBot] [Ixquick] [Lycos] [MAMMA] [Scirus] [Teoma] [WebCrawler] [Wikipedia] [YAHOO]

Visit our Advertisers for Phlogopite :

A Bijoux Google Search for Phlogopite
Adam's Minerals Google Search for Phlogopite
Cape Minerals Google Search for Phlogopite
Dakota Matrix Minerals Google Search for Phlogopite
Excalibur Mineral Corp. Google Search for Phlogopite
Exceptional Minerals Google Search for Phlogopite
John Betts Fine Minerals Search for Phlogopite
McDougall Minerals Google Search for Phlogopite
Mineral News Website Link
Rock and Mineral Shows Google Search for Phlogopite
Weinrich Minerals, Inc. Google Search for Phlogopite

Ask about Phlogopite 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 Phlogopite Specimen Label here :

Phlogopite

KMg3(Si3Al)O10(F,OH)2
Dana No: 71.02.02b.01 Strunz No: 09.EC.20
Locality:

Notes: