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Posnjakite Mineral Data

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General Posnjakite Information

Help on Chemical  Formula: Chemical Formula: Cu4(SO4)(OH)6•(H2O)
Help on Composition: Composition: Molecular Weight = 470.31 gm
   Copper    54.05 %  Cu   67.65 % CuO
   Hydrogen   1.71 %  H    15.32 % H2O
   Sulfur     6.82 %  S    17.02 % SO3
   Oxygen    37.42 %  O
            ______        ______ 
            100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Cu4(SO4)(OH)6•(H2O)
Help on IMA Status: IMA Status: Approved IMA 1967
Help on Locality: Locality: Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named after the geochemist, E. W. Posnjak (1888-1949).
Help on Name Pronunciation: Name Pronunciation: Posnjakite + Pronunciation Say POSNJAKITE
Help on Synonym: Synonym: ICSD 100276
  PDF 43-670
 

Posnjakite Image

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  Posnjakite

Comments: Waxy blue aggregates of posnjakite.
Location: Ecton mine, Audubon, Montgomery County, Pennsylvania, USA. Scale: Not Given.
© Lou Perloff / Photo Atlas of Minerals

Posnjakite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =2.2454:1:1.6673
Help on Cell Dimensions: Cell Dimensions: a = 14.236, b = 6.34, c = 10.571, Z = 4; beta = 102.917° V = 929.96 Den(Calc)= 3.36
Help on Crystal System: Crystal System: Monoclinic - Prismatic H-M Symbol (2/m) Space Group: C 2/c
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 6.94(1), 3.47(0.3), 2.7(0.25),
 

Physical Properties of Posnjakite

Help on Cleavage: Cleavage: {???} Perfect
Help on Color: Color: Blue, Dark blue.
Help on Density: Density: 3.4
Help on Fracture: Fracture: Uneven - Flat surfaces (not cleavage) fractured in an uneven pattern.
Help on Habit: Habit: Crystalline - Fine - Occurs as well-formed fine sized crystals.
Help on Habit: Habit: Encrustations - Forms crust-like aggregates on matrix.
Help on Habit: Habit: Platy - Sheet forms (e.g. micas).
Help on Hardness: Hardness: 2.5-3 - Finger Nail-Calcite
Help on Luster: Luster: Vitreous (Glassy)
Help on Streak: Streak: greenish blue
 

Optical Properties of Posnjakite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= 0 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= -0.011 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1995,KPDmeas= 0.1972,KC= 0.1972
Ncalc = 1.66 - 1.67
Help on Optical Data: Optical Data: Biaxial (-), a=1.625, b=1.68, g=1.706, bire=0.0810, 2V(Calc)=66, 2V(Meas)=57.
 

Calculated Properties of Posnjakite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=3.30 gm/cc
note: Specific Gravity of Posnjakite =3.40 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.00069355
Boson Index = 0.99930645
Help on Photoelectric: Photoelectric: PEPosnjakite = 23.94 barns/electron
U=PEPosnjakite x rElectron Density= 78.94 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Posnjakite is Not Radioactive
 

Posnjakite Classification

Help on  Dana Class: Dana Class: 31.04.01.01 (31)Hydrated Sulfates Containing Hydroxyl or Halogen
  (31.04)where (A+ B++)4 (XO4) Zq�x(H2O)
  (31.04.01)Dana Group
 
31.04.01.01 Posnjakite Cu4(SO4)(OH)6•(H2O) C 2/c 2/m
Help on  Strunz Class: Strunz Class: 07.DD.10 07 - SULFATES (SELENATES, TELLURATES)
  07.D - Sulfates (selenates, etc.) with additional anions, with H2O
  07.DD -With only medium-sized cations; sheets of edge-sharing octahedra
 
07.DD.10 Langite Cu4(SO4)(OH)6•2(H2O) Pc m
 
07.DD.10 Posnjakite Cu4(SO4)(OH)6•(H2O) C 2/c 2/m
 
07.DD.10 Wroewolfeite Cu4(SO4)(OH)6•2(H2O) Pc m
 

Other Posnjakite Information

Help on References: References: NAME( Duda&Rejl90) 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 Posnjakite :
1 - Alkali-Nuts(English)
2 - Alkali-Nuts(Francais)
3 - Am. Min. Crystal Structure Database
4 - Athena
5 - EUROmin Project
6 - Ecole des Mines de Paris
7 - GeoScienceWorld
8 - Google Images
9 - Google Scholar
10 - Handbook of Mineralogy (MinSocAm)
11 - Handbook of Mineralogy (UofA)
12 - MinDAT
13 - Mineralienatlas (Deutsch)
14 - Online Mineral Museum
15 - QUT Mineral Atlas
16 - Ruff.Info
17 - WWW-MINCRYST

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

Posnjakite

Cu4(SO4)(OH)6•(H2O)
Dana No: 31.04.01.01 Strunz No: 07.DD.10
Locality:

 

Notes:

 

 
   
 


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