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Macdonaldite Mineral Data

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General Macdonaldite Information

Help on Chemical  Formula: Chemical Formula: BaCa4[Si16O36(OH)2]•10(H2O)
Help on Composition: Composition: Molecular Weight = 1,537.15 gm
   Barium     8.93 %  Ba    9.97 % BaO
   Calcium   10.43 %  Ca   14.59 % CaO
   Silicon   29.23 %  Si   62.54 % SiO2
   Hydrogen   1.44 %  H    12.89 % H2O
   Oxygen    49.96 %  O
            ______        ______ 
            100.00 %      100.00 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: BaCa4Si16O36(OH)2•10(H2O)
Help on Environment: Environment: Sanbornite-bearing metamorphic rocks near a granodiorite contact.
Help on IMA Status: IMA Status: Approved IMA 1965
Help on Locality: Locality: Big Creek - Rush Creek sanbornite deposit, 5 miles NE of Trimmer, Fresno Co., California. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for Grodon Andrew Macdonald (1911-1978), American volcanologist, University of Hawaii.
Help on Name Pronunciation: Name Pronunciation: Macdonaldite + Pronunciation Say MACDONALDITE
Help on Synonym: Synonym: ICSD 23566
  PDF 18-163
 

Macdonaldite Image

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  Macdonaldite

Comments: Bright white flattened radial macdonaldite aggregate on quartz.
Location: Rush Creek, Fresno County, California, USA. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Macdonaldite Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =0.5977:1:0.5561
Help on Cell Dimensions: Cell Dimensions: a = 14.06, b = 23.52, c = 13.08, Z = 4; V = 4,325.44 Den(Calc)= 2.36
Help on Crystal System: Crystal System: Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: C mcm
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 6.5(1), 4.36(0.8), 6.3(0.5),
 

Physical Properties of Macdonaldite

Help on Cleavage: Cleavage: {010} Perfect, {001} Good, {100} Indistinct
Help on Color: Color: Colorless, White.
Help on Density: Density: 2.27
Help on Diaphaneity: Diaphaneity: Transparent
Help on Habit: Habit: Acicular - Occurs as needle-like crystals.
Help on Hardness: Hardness: 3.5-4 - Copper Penny-Fluorite
Help on Luster: Luster: Vitreous - Silky
Help on Streak: Streak: white
 

Optical Properties of Macdonaldite

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.062 (Fair) - where the CI = (1-KPDmeas/KC)
CI calc= -0.022 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.222,KPDmeas= 0.2308,KC= 0.2173
Ncalc = 1.49 - 1.51
Help on Optical Data: Optical Data: Biaxial (+/-), a=1.518, b=1.524, g=1.53, bire=0.0120, 2V(Calc)=88, 2V(Meas)=90.
 

Calculated Properties of Macdonaldite

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=2.35 gm/cc
note: Specific Gravity of Macdonaldite =2.36 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.02
Boson Index = 0.98
Help on Photoelectric: Photoelectric: PEMacdonaldite = 38.38 barns/electron
U=PEMacdonaldite x rElectron Density= 90.28 barns/cc.
Help on Radioactivity: Radioactivity: GRapi = 0 (Gamma Ray American Petroleum Institute Units)
Macdonaldite is Not Radioactive
 

Macdonaldite Classification

Help on  Dana Class: Dana Class: 72.05.01.03 (72)Phyllosilicate Two-Dimensional Infinite Sheets with Other Than Six-Membered Rings
  (72.05)with corrugated and complex layers
  (72.05.01)Rhodesite group
 
72.05.01.01 Rhodesite KHCa2Si8O19•5(H2O) Pmam 2/m 2/m 2/m
 
72.05.01.02 Monteregianite-(Y) (Na,K)6(Y,Ca)2Si16O38•10(H2O) P 21/m 2/m
 
72.05.01.03 Macdonaldite BaCa4[Si16O36(OH)2]•10(H2O) C mcm 2/m 2/m 2/m
 
72.05.01.04 Delhayelite (Na,K)10Ca5Al6Si32O80(Cl2,F2,SO4)3•18(H2O) Pnmm 2/m 2/m 2/m
 
72.05.01.05 Hydrodelhayelite KCa2AlSi7O17(OH)2•6(H2O) Pnm21 mm2
 
72.05.01.06 Seidite-(Ce)! Na4(Ce,Sr)2{Ti(OH)2(Si8O18)}(O,OH,F)4•5(H2O) C/2c 2/m
Help on  Strunz Class: Strunz Class: 09.EB.05 09 - SILICATES (Germanates)
  09.E - Phyllosilicates
  09.EB -Double nets with 4- and 6-membered rings
 
09.EB.05 Macdonaldite BaCa4[Si16O36(OH)2]•10(H2O) C mcm 2/m 2/m 2/m
 
09.EB.05 Rhodesite KHCa2Si8O19•5(H2O) Pmam 2/m 2/m 2/m
 

Other Macdonaldite Information

Help on References: References: NAME( MinRec) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)
Help on See Also: See Also: Links to other databases for Macdonaldite :
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
15 - WWW-MINCRYST

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

Macdonaldite

BaCa4[Si16O36(OH)2]•10(H2O)
Dana No: 72.05.01.03 Strunz No: 09.EB.05
Locality:

 

Notes:

 

 
   
 


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