Allanite-(La) Mineral Data

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General Allanite-(La) Information

Chemical Formula:

Ca(REE,Ca)Al2(Fe++,Fe+++)(SiO4)(Si2O7)O(OH)

Composition:

Molecular Weight = 557.74 gm

Calcium 9.19 % Ca 12.86 % CaO

Lanthanum 7.17 % La 8.41 % La₂O₃

Cerium 5.18 % Ce 6.06 % Ce₂O₃

Praeseodymium 2.68 % Pr 3.13 % Pr₂O₃

Yttrium 0.02 % Y 0.02 % Y₂O₃

Thorium 0.25 % Th 0.28 % ThO₂

Magnesium 0.19 % Mg 0.32 % MgO

Titanium 0.06 % Ti 0.10 % TiO₂

Aluminum 9.29 % Al 17.56 % Al₂O₃

Iron 10.50 % Fe 8.50 % FeO / 5.30 % Fe₂O₃

Silicon 15.00 % Si 32.08 % SiO₂

Hydrogen 0.18 % H 1.62 % H₂O

Neodymium 3.00 % Nd 3.50 % Nd₂O₃

Oxygen 37.29 % O

______ ______

100.00 % 99.74 % = TOTAL OXIDE

Empirical Formula:

CaLa_0.28Ce_0.2Nd_0.11Pr_0.1Y_0.001Ca_0.27Th_0.006Al_0.89Fe³⁺_0.1AlFe²⁺_0.66Fe³⁺_0.27Mg_0.04 Ti_0.007Si_0.97Al_0.02O₄(Si₂O₇)O(OH)

Environment:

Found in close association with calcite and barite in barite veins that cut a dolomitic metamorphosed limestone. Epidote group.

IMA Status:

Approved IMA 2003 (Dana # Added)

Locality:

Buca della Vena Mine, Stazzema, Apuan Alps, Lucca Province, Tuscany, Italy. Link to MinDat.org Location Data.

Name Origin:

Named after the Scottish mineralogist, T. Allan (1777-1833) and the La content.

Name Pronunciation:

Allanite-(La)

Synonym:

IMA2003-065

Allanite-(La) Image

Images:

Allanite-(La)

Comments: A single prismatic allanite-(La) crystal with small, lustrous black magnetite crystals, all on a matrix of hedenbergite.
Location: Mina Nueva Vizcaya, Sierra Gorda, Burguillos del Cerro, Badajoz, Spain. Scale: Crystal size 0.9 x 0.5 cm.
© Fabre Minerals

Allanite-(La) Crystallography

Axial Ratios:

a:b:c =1.5567:1:1.7694

Cell Dimensions:

a = 8.914, b = 5.726, c = 10.132, Z = 2; beta = 114.87° V = 469.19 Den(Calc)= 3.95

Crystal System:

Monoclinic - PrismaticH-M Symbol (2/m) Space Group: P 2₁/m

$Help on X Ray Diffraction:$ X Ray Diffraction:

By Intensity(I/I_o): 2.901(1)(113), 2.692(0.6)(013 ), 2.611(0.5)(311), 2.806(0.4)(020 ), 2.174(0.25)(401), 1.632(0.2)(233), 3.506(0.2)(211), 1.432(0

Crystal Structure:

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drag2 - RMB Resize/Rotate
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Orlandi P , Pasero M , The Canadian Mineralogist , 44 (2006) p.63-68, Allanite-(La) from Buca della Vena mine, Apuan Alps, Italy, an epidote-group mineral, Locality: Buca della Vena mine, near Stazzema, Apuan Alps, Tuscany, Italy

Physical Properties of Allanite-(La)

Color:

Brown, Black.

Density:

3.93

Diaphaneity:

Transparent to translucent

Fracture:

Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.

Habit:

Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).

Hardness:

6 - Orthoclase

Luminescence:

Radioactive and Non-Fluorescent.

Luster:

Vitreous (Glassy)

Streak:

grayish brown

Optical Properties of Allanite-(La)

Gladstone-Dale:

CI meas= 0.034 (Excellent) - where the CI = (1-KPDmeas/KC)
CI calc= 0.039 (Excellent) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1924,KPDmeas= 0.1934,KC= 0.2002
Ncalc = 1.79

Optical Data:

Biaxial (-), a=1.755, b=1.76, g=1.765, bire=0.0100

Calculated Properties of Allanite-(La)

Electron Density:

Bulk Density (Electron Density)=3.77 gm/cc
note: Specific Gravity of Allanite-(La) =3.93 gm/cc.

Fermion Index:

Fermion Index = 0.01
Boson Index = 0.99

Photoelectric:

PE_{Allanite-(La)}= 98.10 barns/electron
U=PE_{Allanite-(La)} x r_electron= 369.64 barns/cc.

Radioactivity:

GRapi = 5,105.45 (Gamma Ray American Petroleum Institute Units)
Concentration of Allanite-(La) per GRapi unit = 195.87 (PPM)

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

**Estimated Radioactivity from Allanite-(La)** - mild
Specimen Size Weight/Volume (Sphere) *	Calculated Activity Bequerols (Bq)	Calculated Activity Curies (Ci)	Estimated Activity GR(api)	Estimated Exposure (mRem**)/hr If Held in Hand For One Hour
1000 gm / 7.86 cm	111,830	3.02E-06	5,105.45	1.68
100 gm / 3.65 cm	11,183	3.02E-07	510.54	0.17
10 gm / 1.69 cm	1,118	3.02E-08	51.05	0.02
1 gm / 7.86 mm	112	3.02E-09	5.11	0.00
0.1 gm / 3.65 mm	11	3.02E-10	0.51	0.00
0.01 gm / 1.69 mm	1	3.02E-11	0.05	0.00
0.001 gm / 0.79 mm	0	3.02E-12	0.01	0.00

Weight of pure Allanite-(La) in grams (gm) and Calculated Diameter of a Sphere with a Density of 3.93 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

Allanite-(La) Classification

Dana Class:

58.02.01c.02 (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

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 Allanite-(La) Information

References:

NAME( AmMin, v91, p1945) PHYS. PROP.(AmMin, v91, p1945) OPTIC PROP.(AmMin, v91, p1945)

See Also:

Links to other databases for Allanite-(La) :
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 - MinDAT
9 - Mineralienatlas (Deutsch)
10 - Online Mineral Museum
11 - QUT Mineral Atlas
12 - Ruff.Info

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Print or Cut-and-Paste your Allanite-(La) Specimen Label here :

Allanite-(La)

Ca(REE,Ca)Al2(Fe++,Fe+++)(SiO4)(Si2O7)O(OH)
Dana No: 58.02.01c.02 Strunz No: 09.BG.05b
Locality:

Notes: