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Dissakisite-(Ce) Mineral Data

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General Dissakisite-(Ce) Information

Help on Chemical  Formula: Chemical Formula: Ca(Ce,REE)(Mg,Fe++)(Al,Fe+++)2Si3O12(OH)
Help on Composition: Composition: Molecular Weight = 599.36 gm
   Calcium           6.69 %  Ca    9.36 % CaO
   Cerium           10.52 %  Ce   12.32 % Ce2O3
   La,Ce,Pr,Nd,Sm,  15.62 %  RE   18.22 % REE2O3
   Magnesium         4.46 %  Mg    7.40 % MgO
   Aluminum          5.40 %  Al   10.21 % Al2O3
   Iron              8.39 %   Fe    5.39 % FeO /  5.99 % Fe2O3
   Silicon          14.06 %  Si   30.07 % SiO2
   Hydrogen          0.17 %  H     1.50 % H2O
   Oxygen           34.70 %  O
                   ______        ______ 
                   100.00 %      100.47 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: CaCe0.45REE0.65Mg1.1Fe2+0.45Al1.2Fe3+0.45Si3O12(OH)
Help on Environment: Environment: Formed in marble under amphibolite-facies metamorphism (600 deg C and 7 Kbar).
Help on IMA Status: IMA Status: Approved IMA 1991- Dana Number Modified from 58.2.1a.5
Help on Locality: Locality: On the Balchen Mountain, Sor Rondane Mountains, east Antarctica. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: From the Greek for "twice over," for a magnesium analog of allanite being described twice.
Help on Synonym: Synonym: ICSD 75920
  PDF 47-1788

Dissakisite-(Ce) Image

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  Dissakisite-(Ce)   Dolomite

Comments: Small, prisimatic, acicular crystals of tan-colored dissakisite-(Ce) scatterd on white crystalline dolomite.
Location: Trimouns mine, Luzenac, Ariège France. Scale: Picture size 5 cm.
© Fabre Minerals

Dissakisite-(Ce) Crystallography

Help on Axial Ratios: Axial Ratios: a:b:c =1.5642:1:1.7789
Help on Cell Dimensions: Cell Dimensions: a = 8.916, b = 5.7, c = 10.14, Z = 2; beta = 114.72° V = 468.10 Den(Calc)= 4.25
Help on Crystal System: Crystal System: Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 21/m
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.698(1), 2.91(0.9), 2.622(0.6),

Physical Properties of Dissakisite-(Ce)

Help on Cleavage: Cleavage: {001} Good
Help on Color: Color: Yellow brown, Reddish brown.
Help on Density: Density: 3.75
Help on Diaphaneity: Diaphaneity: Transparent
Help on Habit: Habit: Anhedral Grains - Granular minerals without the expression of crystal shapes
Help on Hardness: Hardness: 6.5-7 - Pyrite-Quartz
Help on Luster: Luster: Vitreous (Glassy)
Help on Streak: Streak: white

Optical Properties of Dissakisite-(Ce)

Help on Gladstone-Dale: Gladstone-Dale: CI meas= -0.025 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.096 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1752,KPDmeas= 0.1986,KC= 0.1937
Ncalc = 1.73 - 1.82
Help on Optical Data: Optical Data: Biaxial (+), a=1.735, b=1.741, g=1.758, bire=0.0230, 2V(Calc)=62, 2V(Meas)=64.2. Dispersion r < v medium.
Help on Pleochroism (x): Pleochroism (x): pale brown.
Help on Pleochroism (y): Pleochroism (y): light yellow brown.
Help on Pleochroism (z): Pleochroism (z): light yellow brown.

Calculated Properties of Dissakisite-(Ce)

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=3.57 gm/cc
note: Specific Gravity of Dissakisite-(Ce) =3.75 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.04
Boson Index = 0.96
Help on Photoelectric: Photoelectric: PEDissakisite-(Ce) = 148.37 barns/electron
U=PEDissakisite-(Ce) x relectron= 529.05 barns/cc.
Help on Radioactivity: Radioactivity:

GRapi = 26,565.28 (Gamma Ray American Petroleum Institute Units)
Concentration of Dissakisite-(Ce) per GRapi unit = 37.64 (PPM)

Dissakisite-(Ce) is Radioactive as defined in 49 CFR 173.403. Greater than 70 Bq / gram.

Estimated Radioactivity from Dissakisite-(Ce) - weak
Curies (Ci)
If Held in Hand
For One Hour
1000 gm / 7.99 cm 586,711 1.59E-05 26,565.28 8.73
100 gm / 3.71 cm 58,671 1.59E-06 2,656.53 0.87
10 gm / 1.72 cm 5,867 1.59E-07 265.65 0.09
1 gm / 7.99 mm 587 1.59E-08 26.57 0.01
0.1 gm / 3.71 mm 59 1.59E-09 2.66 0.00
0.01 gm / 1.72 mm 6 1.59E-10 0.27 0.00
0.001 gm / 0.80 mm 1 1.59E-11 0.03 0.00

Weight of pure Dissakisite-(Ce) in grams (gm) and Calculated Diameter of a Sphere with a Density of 3.75 gm/cc.*
Goverment Estimate of Average Annual Exposure ( 360 mRem) **
Note: 10 microsieverts/hr = 1 mRem/hr **
Max Permissable Adult Dose 50,000 mRem/yr (hands), 15,000 mRem/yr (eyes)
Lethal Dose LD(50) Exposure 400,000 to 500,000 mRem
Estimated Thorium Activity ( 1.31 % Th) From Sum REE Elements (26.14 % REE)

Dissakisite-(Ce) Classification

Help on  Dana Class: Dana Class: 58.02.01c.04 (58)Sorosilicate Insular, Mixed, Single, and Larger Tetrahedral Groups
  (58.02)with cations in [6] and higher coordination; single and double groups (n=1,2)
  (58.02.01c)Epidote group (Allanite subgroup)
58.02.01c.01 Allanite-(Ce) (Ce,Ca,Y)2(Al,Fe)3(SiO4)3(OH) P 21/m 2/m
58.02.01c.02 Allanite-(La)! Ca(REE,Ca)Al2(Fe,Fe)(SiO4)(Si2O7)O(OH) P 21/m 2/m
58.02.01c.03 Allanite-(Y) (Y,Ce,Ca)2(Al,Fe)3(SiO4)3(OH) P 21/m 2/m
58.02.01c.04 Dissakisite-(Ce) Ca(Ce,REE)(Mg,Fe)(Al,Fe)2Si3O12(OH) P 21/m 2/m
58.02.01c.05 Dissakisite-(La)! (Ca,Fe,Th,La)(La,REE,Ca)(Al,Cr,Ti)2(Mg,Fe,Al)Si3O12(OH,F)withLa>Ce P 21/m 2/m
58.02.01c.06 Manganiandrosite-(La)! (Mn,Ca)(La,Ce,Ca,Nd)AlMnMn(SiO4)(Si2O7)O(OH) P 21/m 2/m
58.02.01c.07 Ferriallanite-(Ce)! CaCe(Fe,Fe,Al)3[SiO4][Si2O7]O(OH) P 21/m 2/m
58.02.01c.08 Vastmanlandite-(Ce)! (Ce,La)3CaAl2Mg2[Si2O7][SiO4]3F(OH)2 P 21/m 2/m
58.02.01c.09 Manganiandrosite-(Ce)! (Mn,Ca)(Ce,REE)AlMnMn(Si2O7)(SiO4)O(OH) P 21/m 2/m
58.02.01c.10 Vanadoandrosite-(Ce)! (Mn,Ca)(REE)VAlMn(Si2O7)(SiO4)O(OH) P 21/m 2/m
Help on  Strunz Class: Strunz Class: 09.BG.05b 09 - SILICATES (Germanates)
  09.B - Sorosilicates
  09.BG -Sorosilicates with mixed SiO4 and Si2O7 groups;
09.BG.05b Allanite-(La)! Ca(REE,Ca)Al2(Fe,Fe)(SiO4)(Si2O7)O(OH) P 21/m 2/m
09.BG.05b Allanite-(Y) (Y,Ce,Ca)2(Al,Fe)3(SiO4)3(OH) P 21/m 2/m
09.BG.05b Allanite-(Ce) (Ce,Ca,Y)2(Al,Fe)3(SiO4)3(OH) P 21/m 2/m
09.BG.05b Manganiandrosite-(La)! (Mn,Ca)(La,Ce,Ca,Nd)AlMnMn(SiO4)(Si2O7)O(OH) P 21/m 2/m
09.BG.05b Dissakisite-(Ce) Ca(Ce,REE)(Mg,Fe)(Al,Fe)2Si3O12(OH) P 21/m 2/m
09.BG.05b Manganiandrosite-(Ce)! (Mn,Ca)(Ce,REE)AlMnMn(Si2O7)(SiO4)O(OH) P 21/m 2/m
09.BG.05b Vanadoandrosite-(Ce)! (Mn,Ca)(REE)VAlMn(Si2O7)(SiO4)O(OH) P 21/m 2/m
09.BG.05b Dissakisite-(La)! (Ca,Fe,Th,La)(La,REE,Ca)(Al,Cr,Ti)2(Mg,Fe,Al)Si3O12(OH,F)withLa>Ce P 21/m 2/m
09.BG.05b Ferriallanite-(Ce)! CaCe(Fe,Fe,Al)3[SiO4][Si2O7]O(OH) P 21/m 2/m
09.BG.05b Uedaite-(Ce)! MnCeAl2Fe(Si2O7)(SiO4)O(OH) P 21/m 2/m

Other Dissakisite-(Ce) Information

Help on References: References: NAME( AntBidBlaNic2) PHYS. PROP.(Am.Min.,Vol.76,p1990-1997,1991) OPTIC PROP.(AntBidBlaNic2)
Help on See Also: See Also: Links to other databases for Dissakisite-(Ce) :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - GeoScienceWorld
5 - Google Images
6 - Google Scholar
7 - Handbook of Mineralogy (UofA)
8 - MinDAT
9 - Mineralienatlas (Deutsch)
10 - Online Mineral Museum
11 - QUT Mineral Atlas
12 - Ruff.Info

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Dana No: 58.02.01c.04 Strunz No: 09.BG.05b





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