Mineralogy Database

Cohenite Mineral Data

Search Webmineral :

General Cohenite Information

Help on Chemical  Formula: Chemical Formula: (Fe,Ni,Co)3C
Help on Composition: Composition: Molecular Weight = 183.04 gm
   Iron    54.92 %  Fe
   Cobalt   9.66 %  Co
   Nickel  28.86 %  Ni
   Carbon   6.56 %  C
          100.00 % 
Help on Empirical Formula: Empirical Formula: Fe0+1.8Ni0.9Co0.3C
Help on Environment: Environment: In iron meteorites, also in terrestrial iron, in mafic rocks chemically reduced from the assimilation of graphite.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1889
Help on Locality: Locality: Common in iron meteorites. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Emil Wilhelm Cohen (1842-1905), Professor of Mineralogy, University of Greifswald, Greifswald, Germany.
Help on Synonym: Synonym: ICSD 16593
  PDF 35-772

Cohenite Image

Click Here for Larger   Image in a New Browser Window Images:
Click Here for Larger   Image


Comments: Bluish gray, metallic iridescent crystals of cohenite on matrix.
Location: Kopeisk, Chelyabinsk Oblast', Urals Region, Russia. Scale: 2.3 mm.
© Thomas Witzke / Abraxas-Verlag

Click Here for Larger   Image in a New Browser Window Images:
Click Here for Larger   Image

  Troilite   Cohenite   Kamacite   Taenite

Comments: Brown masses of troilite, with white cohenite, in kamacite/taenite matrix, in meteorite (polished section).
Location: Meteor Crater, Canyon Diablo, Coconino County, Arizona, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Cohenite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.8913:1:1.3288
Help on Cell Dimensions: Cell Dimensions: a = 4.518, b = 5.069, c = 6.736, Z = 4; V = 154.27 Den(Calc)= 7.88
Help on Crystal System: Crystal System: Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Pbnm
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.01(1), 2.06(0.7), 2.38(0.65),

Physical Properties of Cohenite

Help on Cleavage: Cleavage: {???} Good, {???} Good, {???} Good
Help on Color: Color: Yellowish white.
Help on Density: Density: 7.2 - 7.65, Average = 7.42
Help on Diaphaneity: Diaphaneity: Opaque
Help on Fracture: Fracture: Brittle - Generally displayed by glasses and most non-metallic minerals.
Help on Hardness: Hardness: 5.5-6 - Knife Blade-Orthoclase
Help on Luster: Luster: Metallic
Help on Magnetism: Magnetism: Strongly magnetic

Optical Properties of Cohenite

Help on RL Color: RL Color: Tin-white.
Help on Reflectivity Reflectivity
Standardized Intensity (100%) Reflection Spectra of Cohenite in Air
λ R1 R2  ∑ R1(λ)   ∑ R2(λ) 
 400 nm   51.80   54.70 
 420 nm   52.60   55.20 
 440 nm   53.20   55.70 
 460 nm   53.80   56.20 
 480 nm   54.40   56.70 
 500 nm   55.00   57.10 
 520 nm   55.60   57.70 
 540 nm   56.20   58.20 
 560 nm   56.80   58.80 
 580 nm   57.40   59.30 
 600 nm   58.00   60.00 
 620 nm   58.70   60.60 
 640 nm   59.30   61.30 
 660 nm   60.00   62.00 
 680 nm   60.80   62.80 
 700 nm   61.60   63.60 
Calculated Relative Intensity Colors of Cohenite in Air
   0%   20%   40%   60%   80% 100% 120% 140% 160% 170%

Calculated Properties of Cohenite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=7.41 gm/cc
note: Specific Gravity of Cohenite =7.88 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.01
Boson Index = 0.99
Help on Photoelectric: Photoelectric: PECohenite = 32.09 barns/electron
U=PECohenite x rElectron Density= 237.86 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Cohenite is Not Radioactive

Cohenite Classification

Help on  Dana Class: Dana Class: (01)Native Elements
  (01.01)with metallic elements other than the platinum group
  (01.01.16)Dana Group Cohenite (Fe,Ni,Co)3C Pbnm 2/m 2/m 2/m Haxonite (Fe,Ni)23C6 F m3m 4/m 3 2/m Isovite! (Cr,Fe)23C6 F m3m 4/m 3 2/m
Help on  Strunz Class: Strunz Class: 01.BA.05 01 - ELEMENTS (Metals and intermetallic alloys; metalloids and nonmetals; carbides, silicides, nitrides, phosphides)
  01.B - Metallic Carbides, Silicides, Nitrides and Phosphides
  01.BA -Carbides
01.BA.05 Cohenite (Fe,Ni,Co)3C Pbnm 2/m 2/m 2/m

Other Cohenite Information

Help on References: References: NAME( AntBidBlaNic3) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic3)
Help on See Also: See Also: Links to other databases for Cohenite :
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 Cohenite using:

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

Visit our Advertisers for Cohenite :

Ask about Cohenite 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 Espaņol

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


Dana No: Strunz No: 01.BA.05





Dakota Matrix
Excalibur Minerals
Exceptional Minerals
Hudson Insitute
John Betts Fine Minerals
Mc Dougall Minerals
Mineral News
Rock and Mineral Shows
Weinrich Minerals, Inc.