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Shigaite Mineral Data

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General Shigaite Information

Help on Chemical  Formula: Chemical Formula: Mn++7Al4(SO4)2(OH)22•8(H2O)
Help on Composition: Composition: Molecular Weight = 1,202.90 gm
   Manganese  31.97 %  Mn   41.28 % MnO
   Aluminum    8.97 %  Al   16.95 % Al2O3
   Hydrogen    3.18 %  H    28.46 % H2O
   Sulfur      5.33 %  S    13.31 % SO3
   Oxygen     50.54 %  O
             ______        ______ 
             100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Mn2+7Al4(SO4)2(OH)22•8(H2O)
Help on Environment: Environment: Found in manganosite-rhodocrosite-sonolite ore.
Help on IMA Status: IMA Status: Approved IMA 1985
Help on Locality: Locality: Loi mine, Shinga Prefecture, Japan. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for the locality.
Help on Name Pronunciation: Name Pronunciation: Shigaite Say SHIGAITE
Help on Synonym: Synonym: ICSD 82492
  PDF 38-428
 

Shigaite Image

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  Shigaite   Pyrochroite

Comments: Bronzy yellow crystals of shigaite set in a crystalline matrix of reddish black pychroite.
Location: N'Chwaning Mine, Kalahari Manganese Field, Northern Cape Province, South Africa. Scale: 2.8 x 2.3 cm.
© John Veevaert

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  Shigaite

Comments: Cluster of sharp, transparent crystals of brown shigaite to 1.2 cm across.
Location: N'Chwaning mine. South Africa. Scale: Aggregate size 1.2 cm.
© John Veevaert

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  Shigaite

Comments: Hexagonal aggregate of orange platy shigaite crystals on a jpale pink rhodocrosite matrix.
Location: N'Chwaning mine. South Africa. Scale: Crystal size 3 mm.
© Sandro Maggia/Minernet.it

Shigaite Crystallography

Help on Axial Ratios: Axial Ratios: a:c = 1:3.47708
Help on Cell Dimensions: Cell Dimensions: a = 9.512, c = 33.074, Z = 3; V = 2,591.56 Den(Calc)= 2.31
Help on Crystal System: Crystal System: Trigonal - Rhombohedral H-M Symbol ( 3) Space Group: R 3
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 10.98(1), 2.547(0.9), 5.47(0.9),
 

Physical Properties of Shigaite

Help on Cleavage: Cleavage: {0001} Perfect, {0001} Good
Help on Color: Color: Light yellow, Orange.
Help on Density: Density: 2.32
Help on Diaphaneity: Diaphaneity: Transparent to Translucent
Help on Fracture: Fracture: Flexible - Flexible fragments.
Help on Habit: Habit: Hexagonal - Six-sided crystal shape in cross-section or habit.
Help on Habit: Habit: Tabular - Form dimensions are thin in one direction.
Help on Hardness: Hardness: 2 - Gypsum
Help on Luminescence: Luminescence: Non-fluorescent.
Help on Streak: Streak: yellow white
 

Optical Properties of Shigaite

Help on Dichroism (e): Dichroism (e): very light yellow.
Help on Dichroism (w): Dichroism (w): light yellow.
Help on Gladstone-Dale: Gladstone-Dale: CI meas= 0.006 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= 0.002 (Superior) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2364,KPDmeas= 0.2353,KC= 0.2367
Ncalc = 1.55
Help on Optical Data: Optical Data: Uniaxial (-), w=1.546.
 

Calculated Properties of Shigaite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.31 gm/cc
note: Specific Gravity of Shigaite =2.31 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.0006472376
Boson Index = 0.9993527624
Help on Photoelectric: Photoelectric: PEShigaite = 8.58 barns/electron
U=PEShigaite x rElectron Density= 19.81 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Shigaite is Not Radioactive
 

Shigaite Classification

Help on  Dana Class: Dana Class: 31.01.02.01 (31)Hydrated Sulfates Containing Hydroxyl or Halogen
  (31.01)where (A+ B++)m (XO4)p Zq�x(H2O), where m:p>6:1
  (31.01.02)Dana Group
 
31.01.02.01 Shigaite Mn7Al4(SO4)2(OH)22•8(H2O) R 3 3
 
31.01.02.02 Nikischerite! NaFe6Al3(SO4)2(OH)18(H2O)12 R 3 3
Help on  Strunz Class: Strunz Class: 07.DD.35 07 - SULFATES (SELENATES, TELLURATES)
  07.D - Sulfates (selenates, etc.) with additional anions, with H2O
  07.DD -With only medium-sized cations; sheets of edge-sharing octahedra
 
07.DD.35 Carrboydite (Ni,Cu)14Al9(SO4,CO3)6(OH)43•7(H2O) Unk Hex
 
07.DD.35 Glaucocerinite (Zn,Cu)5Al3(SO4)1.5(OH)16•9(H2O) Unk (HEX-R) Trig
 
07.DD.35 Honessite Ni6Fe2(SO4)(OH)16•4(H2O) R 3m 3 2/m
 
07.DD.35 Hydrowoodwardite! Cu1-xAlx(OH)2(SO4)x/2•n(H2O)with0<x<0.67andn>3x/2 R 3m 3 2/m
 
07.DD.35 Zincowoodwardite! [Zn1-xAlx(OH)2][(SO4)x/2(H2O)n] P 3- or R 3m 3
 
07.DD.35 Hydrohonessite Ni6Fe2(SO4)(OH)16•7(H2O) Unk Hex
 
07.DD.35 Motukoreaite Na2Mg38Al24(CO3)13(SO4)8(OH)108•56(H2O) R 3m 3 2/m
 
07.DD.35 Mountkeithite (Mg,Ni)11(Fe,Cr)3(SO4,CO3)3.5(OH)24•11(H2O) Unk Hex
 
07.DD.35 Shigaite Mn7Al4(SO4)2(OH)22•8(H2O) R 3 3
 
07.DD.35 Natroglaucocerinite! (Na,Zn,Cu)10Al6(SO4)3(OH)32•18(H2O)? Unk
 
07.DD.35 Wermlandite (Ca,Mg)Mg7(Al,Fe)2(SO4)2(OH)18•12(H2O) P 3c1 3 2/m
 
07.DD.35 Nikischerite! NaFe6Al3(SO4)2(OH)18(H2O)12 R 3 3
 
07.DD.35 Zincaluminite Zn6Al6(SO4)2(OH)26•5(H2O) Unk Hex
 
07.DD.35 Woodwardite Cu4Al2(SO4)(OH)12•2-4(H2O) Unk Hex
 
07.DD.35 Zincowoodwardite-3R! [Zn1BxAlx(OH)2][(SO4)x/2•n(H2O)],0.32<x<0.50,n=0.59 R 3m 3 2/m
 
07.DD.35 Zincowoodwardite-1T! [Zn1BxAlx(OH)2][(SO4)x/2•n(H2O)],x=0.33,n.0.96 P 3 3
 

Other Shigaite Information

Help on References: References: NAME( Dana8) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Dana8)
Help on See Also: See Also: Links to other databases for Shigaite :
1 - Alkali-Nuts(English)
2 - Alkali-Nuts(Francais)
3 - Am. Min. Crystal Structure Database
4 - Athena
5 - EUROmin Project
6 - Ecole des Mines de Paris
7 - GeoScienceWorld
8 - Google Images
9 - Google Scholar
10 - Handbook of Mineralogy (MinSocAm)
11 - Handbook of Mineralogy (UofA)
12 - MinDAT
13 - Mineralienatlas (Deutsch)
14 - Online Mineral Museum
15 - QUT Mineral Atlas
16 - Ruff.Info
17 - WWW-MINCRYST

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

Shigaite

Mn++7Al4(SO4)2(OH)22•8(H2O)
Dana No: 31.01.02.01 Strunz No: 07.DD.35
Locality:

 

Notes:

 

 
   
 


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