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Dorrite Mineral Data

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General Dorrite Information

Help on Chemical  Formula: Chemical Formula: Ca2Mg2Fe+++4(Al,Fe+++)4Si2O20
Help on Composition: Composition: Molecular Weight = 893.97 gm
   Calcium     8.97 %  Ca   12.55 % CaO
   Magnesium   5.44 %  Mg    9.02 % MgO
   Aluminum    6.04 %  Al   11.41 % Al2O3
   Iron       37.48 %  Fe   53.59 % Fe2O3
   Silicon     6.28 %  Si   13.44 % SiO2
   Oxygen     35.79 %  O
             ______        ______ 
             100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Ca2Mg2Fe3+6Al2Si2O20
Help on Environment: Environment: Occurs in a paralava (pyrometamorhic melt rock) formed from burning coal beds.
Help on IMA Status: IMA Status: Approved IMA 1988
Help on Locality: Locality: Druham ranch, 25 km S of Gillette in the Powder River Basin, Wyoming. USA. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for John A. Dorr (1922-1986), University of Michigan.
Help on Name Pronunciation: Name Pronunciation: Dorrite Say DORRITE

Dorrite Image

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Comments: Dark brown micaceous dorrite (arrow) on matrix.
Location: Eicher, Sattel, Baden-Wurttemberg, Germany. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Dorrite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.964:1:0.8276
Help on Cell Dimensions: Cell Dimensions: a = 10.505, b = 10.897, c = 9.019, Z = 2; alpha = 106.26°, beta = 95.16°, gamma = 124.75° V = 811.06 Den(Calc)= 3.66
Help on Crystal System: Crystal System: Triclinic Space Group: P1,P 1
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.971(1), 2.515(0.8), 2.558(0.8),

Physical Properties of Dorrite

Help on Cleavage: Cleavage: {001} Distinct, {010} Distinct
Help on Color: Color: Brownish black, Dark brown, Reddish brown.
Help on Diaphaneity: Diaphaneity: Subopaque
Help on Fracture: Fracture: Irregular - Flat surfaces (not cleavage) fractured in an irregular pattern.
Help on Habit: Habit: Anhedral Grains - Granular minerals without the expression of crystal shapes
Help on Habit: Habit: Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Help on Hardness: Hardness: 5 - Apatite
Help on Luster: Luster: Sub Metallic

Optical Properties of Dorrite

Help on Gladstone-Dale: Gladstone-Dale: CI calc= 0.174 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2188,KC= 0.2648
Ncalc = 2.02
Help on Optical Data: Optical Data: Biaxial (-), a=1.82, b=1.84, g=1.86, bire=0.0400, 2V(Calc)=88, 2V(Meas)=90.
Help on Pleochroism (x): Pleochroism (x): red-orange brown.
Help on Pleochroism (y): Pleochroism (y): yellowish brown.
Help on Pleochroism (z): Pleochroism (z): greenish brown.

Calculated Properties of Dorrite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=3.73 gm/cc
note: Specific Gravity of Dorrite =3.84 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.01
Boson Index = 0.99
Help on Photoelectric: Photoelectric: PEDorrite = 12.91 barns/electron
U=PEDorrite x rElectron Density= 48.12 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Dorrite is Not Radioactive

Dorrite Classification

Help on  Dana Class: Dana Class: 69.02.01a.02 (69)Inosilicate Chains with Side Branches or Loops
  (69.02)with P>2
  (69.02.01a)Aenigmatite and related species (Aenigmatite subgroup)
69.02.01a.01 Aenigmatite (Na,Ca)4(Fe,Ti,Mg)12Si12O40 P1 1
69.02.01a.02 Dorrite Ca2Mg2Fe4(Al,Fe)4Si2O20 P1,P 1 Tri
69.02.01a.03 Hogtuvaite (Ca,Na)2(Fe,Fe,Ti,Mg,Mn)6(Si,Be,Al)6O20 P1 1
69.02.01a.04 Krinovite NaMg2CrSi3O10 P1 1
69.02.01a.05 Rhonite Ca2(Mg,Fe,Fe,Ti)6(Si,Al)6O20 P1 1
69.02.01a.06 Serendibite Ca2(Mg,Al)6(Si,Al,B)6O20 P1 1
69.02.01a.07 Welshite Ca4Mg9Sb3O4[Si6Be3AlFe2O36] P1 1
69.02.01a.08 Wilkinsonite Na2Fe4Fe2Si6O20 P1 1
69.02.01a.09 Makarochkinite! Ca2Fe4FeTiSi4BeAlO20 P1 1
Help on  Strunz Class: Strunz Class: 09.DH.45 09 - SILICATES (Germanates)
  09.D - Inosilicates* Structural terminology according to Liebau (1985)
  09.DH -Inosilicates with 4-periodic single chains, Si4O12
09.DH.45 Aenigmatite (Na,Ca)4(Fe,Ti,Mg)12Si12O40 P1 1
09.DH.45 Dorrite Ca2Mg2Fe4(Al,Fe)4Si2O20 P1,P 1 Tri
09.DH.45 Krinovite NaMg2CrSi3O10 P1 1
09.DH.45 Rhonite Ca2(Mg,Fe,Fe,Ti)6(Si,Al)6O20 P1 1
09.DH.45 Sapphirine (Mg,Al)8(Al,Si)6O20 P1 1
09.DH.45 Serendibite Ca2(Mg,Al)6(Si,Al,B)6O20 P1 1
09.DH.45 Khmaralite! (Mg,Al,Fe)16(Al,Si,Be)12O40 P 21/c 2/m
09.DH.45 Makarochkinite! Ca2Fe4FeTiSi4BeAlO20 P1 1
09.DH.45 Welshite Ca4Mg9Sb3O4[Si6Be3AlFe2O36] P1 1
09.DH.45 Wilkinsonite Na2Fe4Fe2Si6O20 P1 1

Other Dorrite Information

Help on References: References: NAME( Dana8) PHYS. PROP.(Dana8) OPTIC PROP.(Dana8)
Help on See Also: See Also: Links to other databases for Dorrite :
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: 69.02.01a.02 Strunz No: 09.DH.45





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