Chromium Mineral Data

Chromium Mineral Data
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General Chromium Information

Help on Chemical Formula: Chemical Formula: Cr
Help on Composition: Composition: Molecular Weight = 52.00 gm
   Chromium 100.00 %  Cr
            ______ 
            100.00 % 
Help on Empirical Formula: Empirical Formula: Cr
Help on Environment: Environment: In heavy sands derived from the contact metamorphic zone between a siliceous marble and ultramafic rock.
Help on IMA Status: IMA Status: Approved IMA 1981
Help on Locality: Locality: Sichuan Province, China. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: From the Greek, chroma = "color", in allusion to the colorful salts of this element.
Help on Synonym: Synonym: ICSD 64711
  PDF 6-694
 

Chromium Image

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

Chromium

Comments: Small silvery-gray metallic grain of native chromium.
Location: Sichuan, China. Scale: Grain size 0.7 mm.
© Thomas Witzke / Abraxas-Verlag

Chromium Crystallography
Help on Cell Dimensions: Cell Dimensions: a = 2.8839, Z = 2; V = 23.99 Den(Calc)= 7.20
Help on Crystal System: Crystal System: Isometric - HexoctahedralH-M Symbol (4/m 3 2/m) Space Group: I m3m
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.039(1), 1.177(0.3), 0.912(0.2),
Click Here for Large Chromium Structure Window 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


Wyckoff R W G , Crystal Structures , 1 (1963) p.7-83, Second edition. Interscience Publishers, New York, New York, Cubic closest packed, ccp, structure

View Additional jPOWD Structure files for Chromium
[1] [2]
 

Physical Properties of Chromium

Help on Color: Color: White.
Help on Density: Density: 7.2
Help on Diaphaneity: Diaphaneity: Opaque
Help on Fracture: Fracture: Brittle - Generally displayed by glasses and most non-metallic minerals.
Help on Hardness: Hardness: 7.5 - Garnet
Help on Luster: Luster: Metallic
 

Optical Properties of Chromium

Help on RL Color: RL Color: White with a yellow tint.
Help on Reflectivity Reflectivity
Standardized Intensity (100%) Reflection Spectra of Chromium in Air
λ R  ∑ R(λ) 
 480 nm   65.30   
 546 nm   67.90 
 589 nm   68.80 
 656 nm   70.00 
Calculated Relative Intensity Colors of Chromium in Air
Relative
Intensity		    0%   20%   40%   60%   80% 100% 120% 140%
R                
 

Calculated Properties of Chromium

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=6.65 gm/cc
note: Specific Gravity of Chromium =7.20 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.09
Boson Index = 0.91
Help on Photoelectric: Photoelectric: PEChromium = 23.26 barns/electron
U=PEChromium x rElectron Density= 154.63 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Chromium is Not Radioactive
 

Chromium Classification
Help on Dana Class: Dana Class: 01.01.12.01 (01)Native Elements
  (01.01)with metallic elements other than the platinum group
  (01.01.12)Dana Group
 
01.01.12.01 Chromium Cr I m3m 4/m 3 2/m
 
01.01.12.02 Chromferide Fe3Cr1-x(x=0,6) P m3m 4/m 3 2/m
 
01.01.12.03 Ferchromide Cr3Fe1-x(x=0,6) P m3m 4/m 3 2/m
Help on Strunz Class: Strunz Class: 01.AE.05 01 - ELEMENTS (Metals and intermetallic alloys; metalloids and nonmetals; carbides, silicides, nitrides, phosphides)
  01.A - Metals and Intermetallic Alloys
  01.AE -Iron-chromium family
 
01.AE.05 Chromium Cr I m3m 4/m 3 2/m
 
01.AE.05 Kamacite? alpha-(Fe,Ni) F m3m 4/m 3 2/m
 
01.AE.05 Iron Fe I m3m 4/m 3 2/m
 

Other Chromium Information
Help on References: References: NAME( AntBidBlaNic1) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic1)
Help on See Also: See Also: Links to other databases for Chromium :
1 - Am. Min. Crystal Structure Database
2 - Amethyst Galleries' Mineral Gallery
3 - Athena
4 - GeoScienceWorld
5 - Google Images
6 - Google Scholar
7 - Handbook of Mineralogy (MinSocAm)
8 - Handbook of Mineralogy (UofA)
9 - MinDAT
10 - Mineralienatlas (Deutsch)
11 - Online Mineral Museum
12 - QUT Mineral Atlas
13 - Ruff.Info
14 - WWW-MINCRYST

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

Chromium

Cr
Dana No: 01.01.12.01 Strunz No: 01.AE.05
Locality:

 

Notes: