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Drysdallite Mineral Data

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General Drysdallite Information

Help on Chemical  Formula: Chemical Formula: Mo(Se,S)2
Help on Composition: Composition: Molecular Weight = 230.41 gm
   Molybdenum  41.64 %  Mo
   Selenium    51.40 %  Se
   Sulfur       6.96 %  S
              100.00 % 
Help on Empirical Formula: Empirical Formula: MoSe1.5S0.5
Help on Environment: Environment: In the oxidation zone of a uranium deposit in a talc schist.
Help on IMA Status: IMA Status: Approved IMA 1973
Help on Locality: Locality: From the Kapijimpanga uranium deposit, 16 km southeast of Solwezi, Northwestern Province, Zambia. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: For A.R. Drysdall, Director, Geological Survey of Zambia.
Help on Name Pronunciation: Name Pronunciation: Drysdallite + Pronunciation Say DRYSDALLITE

Drysdallite Image

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Comments: Metallic, black, submillimeter crystals of drysdallite approximatly 0.1 mm.
Location: Western Province, Zambia. Scale: Picthure Size 5 mm.
© Sandro Maggia/Minernet.it

Drysdallite Crystallography

Help on Axial Ratios: Axial Ratios: a:c = 1:3.92544
Help on Cell Dimensions: Cell Dimensions: a = 3.286, c = 12.899, Z = 2; V = 120.62 Den(Calc)= 6.34
Help on Crystal System: Crystal System: Hexagonal - Dihexagonal Dipyramidal H-M Symbol (6/m 2/m 2/m) Space Group: P 63/mmc
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.373(1), 6.46(0.76), 2.845(0.55),

Physical Properties of Drysdallite

Help on Cleavage: Cleavage: {0001} Perfect
Help on Color: Color: Grayish black.
Help on Density: Density: 6.25
Help on Diaphaneity: Diaphaneity: Opaque
Help on Hardness: Hardness: 1-1.5 - Talc or a little harder
Help on Luster: Luster: Metallic
Help on Streak: Streak: brown black

Optical Properties of Drysdallite

Help on RL Anisotrophism: RL Anisotrophism: Very strong, with colors from light bluish gray to purplish brown.
Help on RL Color: RL Color: Grayish black with a yellowish tint.
Help on RL Pleochroism: RL Pleochroism: Strong, white to very light gray, to pinkish gray.
Help on Reflectivity Reflectivity
Standardized Intensity (100%) Reflection Spectra of Drysdallite in Air
λ R1 R2  ∑ R1(λ)   ∑ R2(λ) 
 400 nm   17.00   38.00 
 420 nm   18.20   37.80 
 440 nm   19.40   37.60 
 460 nm   20.40   37.60 
 480 nm   21.40   37.50 
 500 nm   21.80   37.50 
 520 nm   21.80   37.40 
 540 nm   21.60   37.10 
 560 nm   21.40   36.70 
 580 nm   21.10   36.00 
 600 nm   20.80   35.50 
 620 nm   20.60   35.10 
 640 nm   20.50   35.00 
 660 nm   20.40   35.00 
 680 nm   20.40   35.20 
 700 nm   20.40   35.60 
Calculated Relative Intensity Colors of Drysdallite in Air
   0%   50% 100% 150% 200% 250% 300% 350% 400% 450%

Calculated Properties of Drysdallite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=5.56 gm/cc
note: Specific Gravity of Drysdallite =6.34 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.14
Boson Index = 0.86
Help on Photoelectric: Photoelectric: PEDrysdallite = 114.13 barns/electron
U=PEDrysdallite x rElectron Density= 634.35 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Drysdallite is Not Radioactive

Drysdallite Classification

Help on  Dana Class: Dana Class: (02)Sulfides - Including Selenides and Tellurides
  (02.12)where Am Bn Xp, with (m+n):p=1:2
  (02.12.10)Molybdenite Group Molybdenite MoS2 P 63/mmc 6/m 2/m 2/m Drysdallite Mo(Se,S)2 P 63/mmc 6/m 2/m 2/m Tungstenite WS2 P 63/mmc 6/m 2/m 2/m
Help on  Strunz Class: Strunz Class: 02.EA.30 02 - SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulf
  02.E - Metal Sulfides, M:S � 1:2
  02.EA -M:S = 1:2
02.EA.30 Drysdallite Mo(Se,S)2 P 63/mmc 6/m 2/m 2/m
02.EA.30 Jordisite MoS2 None
02.EA.30 Molybdenite MoS2 P 63/mmc 6/m 2/m 2/m
02.EA.30 Tungstenite WS2 P 63/mmc 6/m 2/m 2/m

Other Drysdallite 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 Drysdallite :
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: 02.EA.30





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