Hydrobiotite Mineral Data

General Hydrobiotite Information

Chemical Formula:

[K(Mg,Fe)3(Al,Fe)Si3O10(OH,F)2]•[(Mg,Fe++,Al)3(Si,Al)4O10(OH)2•4(H2O)]

Composition:

Molecular Weight = 464.62 gm

Potassium 2.52 % K 3.04 % K₂O

Calcium 0.86 % Ca 1.21 % CaO

Magnesium 12.03 % Mg 19.95 % MgO

Aluminum 6.97 % Al 13.17 % Al₂O₃

Iron 7.21 % Fe 10.31 % Fe₂O₃

Silicon 16.93 % Si 36.21 % SiO₂

Hydrogen 1.69 % H 15.12 % H₂O

Oxygen 50.96 % O

Fluorine 0.82 % F 0.82 % F

- % F -0.34 % -O=F₂

______ ______

100.00 % 99.48 % = TOTAL OXIDE

Empirical Formula:

Mg_2.3Fe³⁺_0.6K_0.3Ca_0.1Si_2.8Al_1.2O₁₀(OH)_1.8F_0.2·3(H₂O)

Environment:

Found in a wide variety of sedimentary environments.

IMA Status:

Valid Species (Pre-IMA) 1882

Locality:

Common world wide. Link to MinDat.org Location Data.

Name Origin:

Named for the water content and its relationship to biotite.

Name Pronunciation:

Hydrobiotite + Pronunciation

Synonym:

Biotitic vermiculite

Hydromica

Jefferisite

Hydrobiotite Image

Images:

Hydrobiotite

Comments: Silvery brown micaceous hydrobiotite.
Location: Oaxaca, Mexico. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Hydrobiotite Crystallography

Axial Ratios:

a:b:c =0.5777:1:2.7222

Cell Dimensions:

a = 5.2, b = 9, c = 24.5, Z = 4; beta = 90° V = 1,146.60 Den(Calc)= 2.69

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): 12.26(1), 3.5(0.5), 3.05(0.2),23.6(0.2), 2.04(0.15), 4.88(0.15), 2.73(0.1), 8.18(0.05),

Physical Properties of Hydrobiotite

Cleavage:

{001} Perfect

Color:

Golden yellow, Black.

Density:

2.49 - 2.64, Average = 2.56

Diaphaneity:

Translucent

Fracture:

Flexible - Flexible fragments.

Hardness:

2.5-3 - Finger Nail-Calcite

Luster:

Sub Metallic

Streak:

white

Optical Properties of Hydrobiotite

Gladstone-Dale:

CI meas= 0.066 (Fair) - where the CI = (1-KPDmeas/KC)
CI calc= 0.11 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2095,KPDmeas= 0.2197,KC= 0.2353
Ncalc = 1.59 - 1.63

Optical Data:

Biaxial (-), b=1.56-1.562, g=1.565-1.567, , 2V(Meas)=10.

Pleochroism (x):

light brown.

Pleochroism (y):

brown.

Pleochroism (z):

brown.

Calculated Properties of Hydrobiotite

Electron Density:

Bulk Density (Electron Density)=2.58 gm/cc
note: Specific Gravity of Hydrobiotite =2.57 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_Hydrobiotite= 3.61 barns/electron
U=PE_Hydrobiotite x r_electron= 9.31 barns/cc.

Radioactivity:

GRapi = 36.65 (Gamma Ray American Petroleum Institute Units)
Concentration of Hydrobiotite per GRapi unit = 2.73 (%)

Estimated Radioactivity from Hydrobiotite - barely detectable

Hydrobiotite Classification

Dana Class:

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

(71.02)with 2:1 Layers

(71.02.02d)Mica Group (Hydromica subgroup)

71.02.02d.01 Hydrobiotite [K(Mg,Fe)3(Al,Fe)Si3O10(OH,F)2]•[(Mg,Fe,Al)3(Si,Al)4O10(OH)2•4(H2O)] C 2/m 2/m

71.02.02d.02 Illite* (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,(H2O)] C 2/m 2/m

71.02.02d.03 Vermiculite (Mg,Fe,Al)3(Al,Si)4O10(OH)2•4(H2O) C 2/m 2/m

71.02.02d.04 Brammallite* (Na,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,(H2O)] C 2/c 2/m

Strunz Class:

09.EC.60 09 - SILICATES (Germanates)

09.E - Phyllosilicates

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

09.EC.60 Aliettite [Mg3Si4O10(OH)2](Ca0.5,Na)0.33(Al,Mg,Fe)2-3(Si,Al)4O10(OH)2•n(H2O) Unk Mono

09.EC.60 Dozyite (Mg7Al2)(Si4Al2)O15(OH)12 Cm m

09.EC.60 Corrensite (Ca,Na,K)(Mg,Fe,Al)9(Si,Al)8O20(OH)10•n(H2O) Unk Ortho

09.EC.60 Kulkeite Na0.35Mg8AlSi7O20(OH)10 Unk Mono

09.EC.60 Karpinskite (Mg,Ni)2Si2O5(OH)2(?) Unk Mono

09.EC.60 Illite* (K,H3O)(Al,Mg,Fe)2(Si,Al)4O10[(OH)2,(H2O)] C 2/m 2/m

09.EC.60 Hydrobiotite [K(Mg,Fe)3(Al,Fe)Si3O10(OH,F)2]•[(Mg,Fe,Al)3(Si,Al)4O10(OH)2•4(H2O)] C 2/m 2/m

09.EC.60 Lunijianlaite LiAl6(Si7Al)O20(OH)10 Unk Mono

09.EC.60 Rectorite (Na,Ca)Al4(Si,Al)8O20(OH)4•2(H2O) Unk Mono

09.EC.60 Saliotite Na0.5Li0.5Al3AlSi3O10(OH)5 C 2/m 2/m

09.EC.60 Tosudite Na0,5(Al,Mg)6(Si,Al)8O18(OH)12•5(H2O) Unk Ortho

09.EC.60 Brinrobertsite! (Na,K,Ca)x(Al,Fe,Mg)4(Si,Al)8O20(OH)4•3.54(H2O)[x=0.35,n=3.54] pseudo 2/m 2/m

Other Hydrobiotite Information

References:

NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Dana8)

See Also:

Links to other databases for Hydrobiotite :
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 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info

Search for Hydrobiotite using:

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

Visit our Advertisers for Hydrobiotite :

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

Ask about Hydrobiotite 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 Hydrobiotite Specimen Label here :

Hydrobiotite

[K(Mg,Fe)3(Al,Fe)Si3O10(OH,F)2]•[(Mg,Fe++,Al)3(Si,Al)4O10(OH)2•4(H2O)]
Dana No: 71.02.02d.01 Strunz No: 09.EC.60
Locality:

Notes: