Margarite Mineral Data

[Fine Minerals] [Events] [Mineral Galleries] [My Collection] [Mineral Auctions]
Full-time professional mineral dealer with over 31 years experience in mineral collecting
And 15 years selling mineral specimens on the internet and at major mineral shows

General Margarite Information

Chemical Formula:

CaAl2(Al2Si2)O10(OH)2

Composition:

Molecular Weight = 398.18 gm

Calcium 10.07 % Ca 14.08 % CaO

Aluminum 27.10 % Al 51.21 % Al₂O₃

Silicon 14.11 % Si 30.18 % SiO₂

Hydrogen 0.51 % H 4.52 % H₂O

Oxygen 48.22 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

CaAl₄Si₂O₁₀(OH)₂

Environment:

Commonly associated with corundum as an alteration product.

IMA Status:

Valid Species (Pre-IMA) 1823

Locality:

Corundum mines at Ekaterinurg Distict, Ural Mountains, Russia. Link to MinDat.org Location Data.

Name Origin:

From the Greek margaritos - "pearl."

Name Pronunciation:

Margarite

Margarite Image

Images:

Margarite

Comments: Beige, massive, fibrous/foliated aggregate of margarite crystals.
Location: Long Hill/Old Tungsten Mine in Trumbull, Connecticut, USA. Scale: 10 x 5 cm.
© Walter Mroch / Gem and Mineral Exploration Company

Margarite Crystallography

Axial Ratios:

a:b:c =0.5816:1:2.1774

Cell Dimensions:

a = 5.118, b = 8.799, c = 19.159, Z = 4; beta = 95.15° V = 859.31 Den(Calc)= 3.08

Crystal System:

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

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

By Intensity(I/I_o): 3.18(1), 1.908(0.35), 2.517(0.25),

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

Guggenheim S , Bailey S W , American Mineralogist , 63 (1978) p.186-187, Refinement of the margarite structure in subgroup symmetry: correction,, further refinement, and comments

Physical Properties of Margarite

Cleavage:

{001} Good

Color:

White, Gray, Pinkish gray, Yellowish gray.

Density:

2.99 - 3.08, Average = 3.03

Diaphaneity:

Translucent to subtranslucent

Fracture:

Brittle - Generally displayed by glasses and most non-metallic minerals.

Habit:

Lamellar - Thin laminae producing a lamellar structure.

Habit:

Massive - Lamellar - Distinctly foliated fine-grained forms.

Habit:

Scaly - Morphology like fish scales.

Hardness:

4 - Fluorite

Luminescence:

Fluorescent, Short UV=sky blue, Long UV=strong sky blue.

Luster:

Pearly

Streak:

white

Optical Properties of Margarite

Gladstone-Dale:

CI meas= 0.028 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.042 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2047,KPDmeas= 0.2077,KC= 0.2137
Ncalc = 1.64 - 1.66

Optical Data:

Biaxial (-), a=1.595-1.638, b=1.625-1.648, g=1.627-1.65, bire=0.0120-0.0320, 2V(Calc)=28-46, 2V(Meas)=26-67. Dispersion r < v.

Pleochroism (x):

colorless.

Pleochroism (y):

colorless.

Pleochroism (z):

colorless.

Calculated Properties of Margarite

Electron Density:

Bulk Density (Electron Density)=3.02 gm/cc
note: Specific Gravity of Margarite =3.04 gm/cc.

Fermion Index:

Fermion Index = 0.0069559576
Boson Index = 0.9930440424

Photoelectric:

PE_Margarite= 2.58 barns/electron
U=PE_Margarite x rElectron Density= 7.79 barns/cc.

Radioactivity:

GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Margarite is Not Radioactive

Margarite Classification

Dana Class:

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

(71.02)with 2:1 Layers

(71.02.02c)Mica Group (Margarite subgroup)

71.02.02c.01 Margarite CaAl2(Al2Si2)O10(OH)2 C 2/c 2/m

71.02.02c.02 Clintonite Ca(Mg,Al)3(Al3Si)O10(OH)2 C 2/m 2/m

71.02.02c.03 Bityite CaLiAl2(AlBeSi2)O10(OH)2 C 2/c 2/m

71.02.02c.04 Anandite (Ba,K)(Fe,Mg)3(Si,Al,Fe)4O10(S,OH)2 C 2/m 2/m

71.02.02c.05 Kinoshitalite (Ba,K)(Mg,Mn,Al)3Si2Al2O10(OH)2 C 2/m 2/m

71.02.02c.06 Ferrokinoshitalite! (Ba,K)(Fe,Mg)3(Si2Al2)O10(OH,F)2 C 2/m 2/m

71.02.02c.07 Ganterite! [Ba0.5(Na,K)0.5]Al2(Si2.5Al1.5O10)(OH)2 C 2/c 2/m

71.02.02c.08 Oxykinoshitalite! (Ba,K)(Mg,Fe,Ti)3(Si,Al)4O10O2 C 2/m 2/m

Strunz Class:

09.EC.30 09 - SILICATES (Germanates)

09.E - Phyllosilicates

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

09.EC.30 Margarite CaAl2(Al2Si2)O10(OH)2 C 2/c 2/m

Other Margarite Information

References:

NAME( Duda&Rejl90) PHYS. PROP.(Collectors Book of Fluorescent Minerals) OPTIC PROP.(Heinrich65)

See Also:

Links to other databases for Margarite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - Franklin Minerals(Dunn)
6 - GeoScienceWorld
7 - Google Images
8 - Google Scholar
9 - Handbook of Mineralogy (MinSocAm)
10 - Handbook of Mineralogy (UofA)
11 - HyperPhysics
12 - MinDAT
13 - Mineralienatlas (Deutsch)
14 - Online Mineral Museum
15 - QUT Mineral Atlas
16 - Ruff.Info
17 - Scandinavian mineral gallery
18 - WWW-MINCRYST

Search for Margarite using:

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

Visit our Advertisers for Margarite :

Dakota Matrix Minerals Google Search for Margarite
John Betts Fine Minerals Search for Margarite
McDougall Minerals Google Search for Margarite
Rock and Mineral Shows Google Search for Margarite
Weinrich Minerals, Inc. Google Search for Margarite

Ask about Margarite 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 Margarite Specimen Label here :

Margarite

CaAl2(Al2Si2)O10(OH)2
Dana No: 71.02.02c.01 Strunz No: 09.EC.30
Locality:

Notes: