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Eglestonite Mineral Data

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General Eglestonite Information

Help on Chemical  Formula: Chemical Formula: Hg6Cl3O(OH) (?)
Help on Composition: Composition: Molecular Weight = 1,342.90 gm
   Mercury   89.62 %  Hg   93.20 % Hg2O
   Hydrogen   0.08 %  H     0.67 % H2O
   Chlorine   7.92 %  Cl    7.92 % Cl
               -   %   Cl   -1.79 % -O=Cl2   
   Oxygen     2.38 %  O
            ______        ______ 
            100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Hg6Cl3O(OH)
Help on Environment: Environment: Secondary mineral associated with mercury deposits
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1903
Help on Locality: Locality: Terlingua district, Brewster County, Texas, USA Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for T. E. Egleston.
Help on Name Pronunciation: Name Pronunciation: Eglestonite + Pronunciation Say EGLESTONITE
Help on Synonym: Synonym: ICSD 12102
  PDF 29-909

Eglestonite Image

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Comments: Small yellow crystals and massive aggregates of eglestonite.
Location: Landsberg (Moschellandsberg), Obermoschel, Palatinate, Rhineland-Palatinate, Germany. Scale: Picture size 0.8 mm.
© Thomas Witzke / Abraxas-Verlag

Eglestonite Crystallography

Help on Cell Dimensions: Cell Dimensions: a = 16.036, Z = 16; V = 4,123.71 Den(Calc)= 8.65
Help on Crystal System: Crystal System: Isometric - Hexoctahedral H-M Symbol (4/m 3 2/m) Space Group: I a3d
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 1.89(1), 3.28(0.9), 2.54(0.6),
Help on Forms: Forms:

Dbl Clk - Start-Stop Rotation
RMB - Cycle Display Modes
Drag1 - Manipulate Crystal
Drag2 - Resize

S - Stereo
I - Indicies
<space> - Start-Stop Rotation
F - Fit to Screen
M - Menu

Help on Above

Forms: ( 1 1 1) ( 1 1 2) ( 2 3 3) ( 0 1 1)

Warning: this java applet does not work in some browsers because of security restrictions.


Physical Properties of Eglestonite

Help on Cleavage: Cleavage: None
Help on Color: Color: Brown, Brownish yellow, Yellow, Dark brown, Orange.
Help on Density: Density: 8.3
Help on Diaphaneity: Diaphaneity: Transparent to translucent
Help on Fracture: Fracture: Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.
Help on Hardness: Hardness: 2-3 - Gypsum-Calcite
Help on Luminescence: Luminescence: Non-fluorescent.
Help on Luster: Luster: Adamantine - Resinous
Help on Magnetism: Magnetism: Nonmagnetic
Help on Streak: Streak: light yellow

Optical Properties of Eglestonite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.111 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.067 (Fair) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1723,KPDmeas= 0.1795,KC= 0.1615
Ncalc = 2.34 - 2.4
Help on Optical Data: Optical Data: Isotropic, n=2.49.

Calculated Properties of Eglestonite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=7.06 gm/cc
note: Specific Gravity of Eglestonite =8.65 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.27
Boson Index = 0.73
Help on Photoelectric: Photoelectric: PEEglestonite =1,554.90 barns/electron
U=PEEglestonite x rElectron Density=10977.02 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Eglestonite is Not Radioactive

Eglestonite Classification

Help on  Dana Class: Dana Class: (10)Oxyhalides and Hydroxyhalides
  (10.05)where Am (O,OH)p Xq
  (10.05.04)Dana Group Eglestonite Hg6Cl3O(OH)(?) I a3d 4/m 3 2/m Kadyrelite Hg4(Br,Cl)2O I a3d 4/m 3 2/m
Help on  Strunz Class: Strunz Class: 03.DD.05 03 - HALIDES
  03.D - Oxyhalides, Hydroxyhalides and Related Double Halides
  03.DD -With Hg
03.DD.05 Eglestonite Hg6Cl3O(OH)(?) I a3d 4/m 3 2/m
03.DD.05 Kadyrelite Hg4(Br,Cl)2O I a3d 4/m 3 2/m

Other Eglestonite Information

Help on References: References: 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 Eglestonite :
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

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


Hg6Cl3O(OH) (?)
Dana No: Strunz No: 03.DD.05





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