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Ernstite Mineral Data

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General Ernstite Information

Help on Chemical  Formula: Chemical Formula: (Mn++1-xFe+++x)Al(PO4)(OH)2-xOx
Help on Composition: Composition: Molecular Weight = 210.86 gm
   Manganese   13.03 %  Mn   16.82 % MnO
   Aluminum    12.80 %  Al   24.18 % Al2O3
   Iron        13.24 %  Fe   18.93 % Fe2O3
   Phosphorus  14.69 %  P    33.66 % P2O5
   Hydrogen     0.72 %  H     6.41 % H2O
   Oxygen      45.53 %  O
              ______        ______ 
              100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Mn2+0.5Fe3+0.5Al(PO4)(OH)1.5O0.5
Help on Environment: Environment: Oxidation product of eosphoite in granitic pegmatite.
Help on IMA Status: IMA Status: Approved IMA 1970
Help on Locality: Locality: Daib-East farm, Karibib, Namibia. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Theodor K. A. Ernst (1904-), mineralogist, University of Erlangen, Germany.
Help on Name Pronunciation: Name Pronunciation: Ernstite Say ERNSTITE

Ernstite Image

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  Ernstite   Schoonerite

Comments: 1 mm honey brown, acicular, radial sprays of ernstite with light green fibrous schoonerite and apatite in siderite.
Location: White Cap mine, Pennington County., South Dakota. Scale: Picture size 3 mm.
© Tom Loomis / Dakota Matrix

Ernstite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =1.326:1:0.6639
Help on Cell Dimensions: Cell Dimensions: a = 13.92, b = 10.497, c = 6.969, Z = 8; beta = 90.37° V = 1,018.28 Den(Calc)= 2.75
Help on Crystal System: Crystal System: Monoclinic Space Group: C 2/c or Cc
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.829(1), 2.836(0.8), 2.438(0.5),

Physical Properties of Ernstite

Help on Cleavage: Cleavage: {010} Good, {100} Good
Help on Color: Color: Yellow brown.
Help on Density: Density: 3.07
Help on Diaphaneity: Diaphaneity: Translucent
Help on Habit: Habit: Aggregates - Made of numerous individual crystals or clusters.
Help on Habit: Habit: Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite)
Help on Hardness: Hardness: 3-3.5 - Calcite-Copper Penny

Optical Properties of Ernstite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.01 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= -0.128 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2552,KPDmeas= 0.2286,KC= 0.2262
Ncalc = 1.62 - 1.69
Help on Optical Data: Optical Data: Biaxial (-), a=1.678, b=1.706, g=1.721, bire=0.0430, 2V(Calc)=70, 2V(Meas)=74. Dispersion r > v.
Help on Pleochroism (x): Pleochroism (x): yellow brown.
Help on Pleochroism (y): Pleochroism (y): red brown.
Help on Pleochroism (z): Pleochroism (z): pale yellow.

Calculated Properties of Ernstite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=3.00 gm/cc
note: Specific Gravity of Ernstite =3.07 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0030271031
Boson Index = 0.9969728969
Help on Photoelectric: Photoelectric: PEErnstite = 8.34 barns/electron
U=PEErnstite x rElectron Density= 25.02 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Ernstite is Not Radioactive

Ernstite Classification

Help on  Dana Class: Dana Class: (42)Hydrated Phosphates, etc., Containing Hydroxyl or Halogen
  (42.07)where (AB)5 (XO4)3 Zq � x(H2O)
  (42.07.01)Childrenite Group Childrenite FeAl(PO4)(OH)2•(H2O) Bba2 mm2 Eosphorite MnAl(PO4)(OH)2•(H2O) Bbam 2/m 2/m 2/m Ernstite (Mn1-xFex)Al(PO4)(OH)2-xOx C 2/c or Cc Mono Sinkankasite H2MnAl(PO4)2(OH)•6(H2O) P1 1
Help on  Strunz Class: Strunz Class: 08.DD.20 08 - PHOSPHATES, ARSENATES, VANADATES
  08.D - Phosphates, etc
  08.DD -With only medium-sized cations, (OH, etc.):RO4 = 2:1
08.DD.20 Childrenite FeAl(PO4)(OH)2•(H2O) Bba2 mm2
08.DD.20 Eosphorite MnAl(PO4)(OH)2•(H2O) Bbam 2/m 2/m 2/m
08.DD.20 Ernstite (Mn1-xFex)Al(PO4)(OH)2-xOx C 2/c or Cc Mono

Other Ernstite Information

Help on References: References: NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Dana8)
Help on See Also: See Also: Links to other databases for Ernstite :
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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Dana No: Strunz No: 08.DD.20





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