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Iddingsite Mineral Data

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General Iddingsite Information

Help on Chemical  Formula: Chemical Formula: MgO.Fe2O3.3SiO2•4(H2O)
Help on Composition: Composition: Molecular Weight = 452.31 gm
   Magnesium   5.37 %  Mg    8.91 % MgO
   Iron       24.69 %  Fe   31.77 % FeO
   Silicon    18.63 %  Si   39.85 % SiO2
   Hydrogen    1.78 %  H    15.93 % H2O
   Oxygen     49.52 %  O
             ______        ______ 
             100.00 %       96.46 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: MgFe2+2Si3O10•4(H2O)
Help on Environment: Environment: Alteration of olivine. Iddinsite is a mixture of various hydrous silicates of iron and magnesium.
Help on IMA Status: IMA Status: Discredited IMA 1966 - Valid Species (Pre-IMA) 1925
Help on Locality: Locality: Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Joseph Paxson Iddings (1857-1920), American petrologist, U.S. Geological Survey.

Iddingsite Image

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Comments: Red iddingsite with green olivine. Iddingsite alteration of olivine commonly seen in thin-sections is actually a fine-grained mixture of goethite+quartz+chlorite.
Location: Amboy, San Bernadino County, California, USA. Scale: Specimen Size 5x5x3 cm.
© John Betts - Fine Minerals

Iddingsite Crystallography

Help on Crystal System: Crystal System: Orthorhombic

Physical Properties of Iddingsite

Help on Cleavage: Cleavage: {???} Perfect
Help on Color: Color: Brown.
Help on Density: Density: 2.5 - 2.8, Average = 2.65
Help on Habit: Habit: Foliated - Two dimensional platy forms.
Help on Hardness: Hardness: 3 - Calcite
Help on Luminescence: Luminescence: Non-fluorescent.

Optical Properties of Iddingsite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.275 (Poor) - where the CI = (1-KPDmeas/KC)
KPDmeas= 0.2736,KC= 0.2146
Ncalc = 1.54 - 1.6
Help on Optical Data: Optical Data: Biaxial (-), a=1.67-1.73, b=1.7-1.76, g=1.72-1.77, bire=0.0400-0.0500

Calculated Properties of Iddingsite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.65 gm/cc
note: Specific Gravity of Iddingsite =2.65 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.01
Boson Index = 0.99
Help on Photoelectric: Photoelectric: PEIddingsite = 8.08 barns/electron
U=PEIddingsite x rElectron Density= 21.41 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Iddingsite is Not Radioactive

Iddingsite Classification

Help on  Dana Class: Dana Class: (78)Unclassified Silicate Minerals
  (78.00)Without Dana Classification Numbers
  (78.00.00)Unclassified Silicate Almbosite? Fe5Fe4V4Si3O27 Ortho ? Ortho Chelyabinskite* (Ca,Mg)3Si(OH)6(SO4,CO3)2•9(H2O) Unk Ortho Cryptophyllite K2Ca[Si4O10]•5H2O P 21/n 2/m IMA2007-041T Na2[Ti4O2(OH)2(SiO4)3]•6H2O R 3m 3m IMA2009-001 Ba5(Ca,REE,Y)22(Ti,Nb)18(SiO4)4[(PO4),(SiO4)]4(BO3)9O22[(OH),F]43(H2O)1.5 R 3 3 Iddingsite? MgO.Fe2O3.3SiO2•4(H2O) Ortho Ivanyukite-Cu Cu[Ti4(OH)2O2(SiO4)3]•7H2O P 4 3m 4 3m Ivanyukite-K K2[Ti4(OH)2O2(SiO4)3]•9H2O P 4 3m 4 3m Ivanyukite-Na Na2[Ti4O2(OH)2(SiO4)3]•6H2O P 4 3m 4 3m Plumbophyllite Pb2Si4O10•H2O P bcn 2/m 2/m 2/m Sturtite? (Fe3)(Mn2,Ca,Mg)Si4O10(OH)3•10(H2O) None
Help on  Strunz Class: Strunz Class: 09.HX.00 09 - SILICATES (Germanates)
  09.H - Unclassified Strunz Silicates
  09.HX -Unclassified Silicate
09.HX.00 Iddingsite? MgO.Fe2O3.3SiO2•4(H2O) Ortho
09.HX.00 IMA2007-041T Na2[Ti4O2(OH)2(SiO4)3]•6H2O R 3m 3m
09.HX.00 Plumbophyllite Pb2Si4O10•H2O P bcn 2/m 2/m 2/m
09.HX.00 Cryptophyllite K2Ca[Si4O10]•5H2O P 21/n 2/m

Other Iddingsite Information

Help on References: References: NAME( Ford32) PHYS. PROP.(Dana) OPTIC PROP.(Heinrich65)
Help on See Also: See Also: Links to other databases for Iddingsite :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info

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Dana No: Strunz No: 09.HX.00





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