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Twinnite Mineral Data

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General Twinnite Information

Help on Chemical  Formula: Chemical Formula: Pb(Sb,As)2S4
Help on Composition: Composition: Molecular Weight = 574.28 gm
   Antimony  40.28 %  Sb
   Arsenic    1.30 %  As
   Lead      36.08 %  Pb
   Sulfur    22.33 %  S
            ______ 
            100.00 % 
Help on Empirical Formula: Empirical Formula: PbSb1.9As0.1S4
Help on Environment: Environment: In marble with other lead sulfantimonides.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1957
Help on Locality: Locality: Madoc, Ontario, Canada. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Robert M. Thompson (1918-1967), Canadian Mineralogist: Thompson means "son of Thomas," which is Aramaic for "twin."
Help on Name Pronunciation: Name Pronunciation: Twinnite Say TWINNITE
Help on Synonym: Synonym: IMA1966-017
 

Twinnite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =2.4537:1:1.073
Help on Cell Dimensions: Cell Dimensions: a = 19.583, b = 7.981, c = 8.564, Z = 8; alpha = 89.767°, beta = 89.617°, gamma = 90.267° V = 1,338.43 Den(Calc)= 5.70
Help on Crystal System: Crystal System: Triclinic - Pinacoidal H-M Symbol ( 1) Space Group: P1
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 3.51(1), 2.344(0.8), 2.78(0.7),
 

Physical Properties of Twinnite

Help on Cleavage: Cleavage: {100} Perfect
Help on Color: Color: Black.
Help on Density: Density: 5.26
Help on Diaphaneity: Diaphaneity: Opaque
Help on Fracture: Fracture: Brittle - Generally displayed by glasses and most non-metallic minerals.
Help on Habit: Habit: Microscopic Crystals - Crystals visible only with microscopes.
Help on Habit: Habit: Twinning Common - Crystals are usually twinned.
Help on Hardness: Hardness: 3.5 - Copper Penny
Help on Luster: Luster: Metallic
Help on Streak: Streak: brownish black
 

Optical Properties of Twinnite

Help on RL Color: RL Color: White.
Help on RL Pleochroism: RL Pleochroism: Strong, displaying twin lamellae.
Help on Reflectivity Reflectivity
Standardized Intensity (100%) Reflection Spectra of Twinnite in Air
λ R1 R2  ∑ R1(λ)   ∑ R2(λ) 
 400 nm   39.10   45.20 
   
 420 nm   38.20   44.70 
 440 nm   37.30   44.20 
 460 nm   36.60   43.70 
 480 nm   36.20   43.20 
 500 nm   35.80   42.90 
 520 nm   35.50   42.50 
 540 nm   35.00   42.00 
 560 nm   34.40   41.40 
 580 nm   34.00   40.80 
 600 nm   33.50   40.00 
 620 nm   33.20   39.40 
 640 nm   32.80   38.70 
 660 nm   32.30   38.10 
 680 nm   31.70   37.50 
 700 nm   31.00   37.00 
Calculated Relative Intensity Colors of Twinnite in Air
Relative
Intensity
   0%   30%   60%   90% 100% 120% 150% 180% 210% 240% 270%
R1                      
R2                      
 

Calculated Properties of Twinnite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=4.89 gm/cc
note: Specific Gravity of Twinnite =5.70 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.08
Boson Index = 0.92
Help on Photoelectric: Photoelectric: PETwinnite = 786.44 barns/electron
U=PETwinnite x rElectron Density=3,843.57 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Twinnite is Not Radioactive
 

Twinnite Classification

Help on  Dana Class: Dana Class: 03.07.08.03 (03)Sulfides - Sulfosalts
  (03.07)where z/y = 2 - (A+)i (A++)j [By Cz], A=metals, B=semi-metals, C=non-metals
  (03.07.08)Sartorite Group
 
03.07.08.01 Sartorite PbAs2S4 P 21/c 2/m
 
03.07.08.02 Guettardite Pb(Sb,As)2S4 P 21/a 2/m
 
03.07.08.03 Twinnite Pb(Sb,As)2S4 P1 1
 
03.07.08.04 Marumoite! Pb32As40S92 P 21 2
Help on  Strunz Class: Strunz Class: 02.HC.05a 02 - SULFIDES and SULFOSALTS (sulfides, selenides, tellurides; arsenides, antimonides, bismuthides; sulfarsenites, sulf
  02.H - Sulfosalts of SnS Archetype
  02.HC -With only Pb
 
02.HC.05a Guettardite Pb(Sb,As)2S4 P 21/a 2/m
 
02.HC.05a Sartorite PbAs2S4 P 21/c 2/m
 
02.HC.05a Twinnite Pb(Sb,As)2S4 P1 1
 

Other Twinnite Information

Help on References: References: NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(AntBidBlaNic1)
Help on See Also: See Also: Links to other databases for Twinnite :
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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Print or Cut-and-Paste your Twinnite Specimen Label here :

Twinnite

Pb(Sb,As)2S4
Dana No: 03.07.08.03 Strunz No: 02.HC.05a
Locality:

 

Notes:

 

 
   
 


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