Gadolinite-(Y) Mineral Data
General Gadolinite-(Y) Information
Chemical Formula:
Y2Fe++Be2Si2O10
Composition:
Molecular Weight = 467.85 gm
Yttrium 38.01 % Y 48.27 % Y2 O3
Beryllium 3.85 % Be 10.69 % BeO
Iron 11.94 % Fe 15.36 % FeO
Silicon 12.01 % Si 25.69 % SiO2
Oxygen 34.20 % O
______ ______
100.00 % 100.00 % = TOTAL OXIDE
Empirical Formula:
Y2 Fe2+ Be2 (Si2 O10 )
Environment:
Pegmatite veins rich in alkaline-earth elements.
IMA Status:
Valid Species (Pre-IMA) 1800
Locality:
Ytterby, Resar�, Sweden. Link to MinDat.org Location Data.
Name Origin:
Named after the Finnish chemist, Johan Gadolin (1760-1852), who discovered
yttrium. The element gadolinium was also named after Johan Gadolin in 1880.
Name Pronunciation:
Gadolinite-(Y) + Pronunciation
Synonym:
Calciogadolinite
ICSD 40095
PDF 26-1134
Gadolinite-(Y) Image
Images:
Gadolinite-(Y) Calciogadolinite
Comments: Black vitreous, metamict massive gadolinite-(Y) also known as calcian gadolinite.
Location: Ytterøya Mine, Røvika, Ytterøya (island), Levanger, Nord-Trondelag, Norway.
Scale: See Image.
© Rruff Database
Gadolinite-(Y) Crystallography
Axial Ratios:
a:b:c =1.3099:1:0.6172
Cell Dimensions:
a = 9.89, b = 7.55, c = 4.66, Z = 2; beta = 90.61° V = 347.94 Den(Calc)= 4.47
Crystal System:
Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 21 /a
X Ray Diffraction:
By Intensity(I/Io ): 2.83(1), 3.13(1), 2.56(0.9),
Physical Properties of Gadolinite-(Y)
Cleavage:
None
Color:
Brown, Green, Green black, Light green, Black.
Density:
4 - 4.5, Average = 4.25
Diaphaneity:
Subtransparent to opaque
Fracture:
Splintery - Thin, elongated fractures produced by intersecting good cleavages or partings (e.g. hornblende).
Habit:
Crystalline - Poor - Occurs primarily as crudely formed crystals.
Habit:
Massive - Uniformly indistinguishable crystals forming large masses.
Habit:
Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Hardness:
6.5-7 - Pyrite-Quartz
Luminescence:
Non-fluorescent.
Luster:
Vitreous - Greasy
Streak:
greenish gray
Optical Properties of Gadolinite-(Y)
Gladstone-Dale:
CI meas = 0.018 (Superior) - where the CI = (1-KPDmeas /KC ) CI calc = 0.066 (Fair) - where the CI = (1-KPDcalc /KC )
KPDcalc = 0.1775,KPDmeas = 0.1867,KC = 0.19 Ncalc = 1.76 - 1.86
Optical Data:
Biaxial (+), a=1.77, b=1.79, g=1.82, bire=0.0500
Calculated Properties of Gadolinite-(Y)
Electron Density:
Bulk Density (Electron Density)=4.00 gm/cc note: Specific Gravity of Gadolinite-(Y) =4.25 gm/cc.
Fermion Index:
Fermion Index = 0.04 Boson Index = 0.96
Photoelectric:
PEGadolinite-(Y) = 51.62 barns/electronU=PEGadolinite-(Y) x r Electron Density= 206.33 barns/cc.
Radioactivity:
GRapi = 0 (Gamma Ray American Petroleum Institute Units) Gadolinite-(Y) is Not Radioactive
Gadolinite-(Y) Classification
Dana Class:
54.02.01b.03 (54) Nesosilicate Borosilicates and Some Beryllosilicates
(54.02) with B in [4] coordination
(54.02.01b) Datolite group (Homilite series)
54.02.01b.01 Bakerite Ca4B4(BO4)(SiO4)3(OH)3•(H2O) P 21 /c 2/m
54.02.01b.02 Gadolinite-(Ce) (Ce,La,Nd,Y)2FeBe2Si2O10 P 21 /c 2/m
54.02.01b.03 Gadolinite-(Y) Y2FeBe2Si2O10 P 21 /a 2/m
54.02.01b.04 Calciogadolinite ? CaREE(Fe)Be2Si2O10 P 21 /a 2/m
54.02.01b.05 Homilite Ca2(Fe,Mg)B2Si2O10 P 21 /a 2/m
54.02.01b.06 Minasgeraisite-(Y) CaY2Be2Si2O10 P 21 /a 2/m
Strunz Class:
09.AJ.20 09 - SILICATES (Germanates)
09.A - Nesosilicates
09.AJ -Nesosilicates with BO3 triangles and/or B[4], Be[4] tetrahedra,
09.AJ.20 Bakerite Ca4B4(BO4)(SiO4)3(OH)3•(H2O) P 21 /c 2/m
09.AJ.20 Calcybeborosilite-(Y) ! (REE,Ca)2[](B,Be)2(SiO4)2(OH,O)2 P 21 /a 2/m
09.AJ.20 Calciogadolinite ? CaREE(Fe)Be2Si2O10 P 21 /a 2/m
09.AJ.20 Datolite CaBSiO4(OH) P 21 /c 2/m
09.AJ.20 Hingganite-(Yb) (Yb,Y)2([])Be2Si2O8(OH)2 P 21 /a 2/m
09.AJ.20 Homilite Ca2(Fe,Mg)B2Si2O10 P 21 /a 2/m
09.AJ.20 Gadolinite-(Ce) (Ce,La,Nd,Y)2FeBe2Si2O10 P 21 /c 2/m
09.AJ.20 Gadolinite-(Y) Y2FeBe2Si2O10 P 21 /a 2/m
09.AJ.20 Hingganite-(Ce) (Ce,Ca)2([],Fe)Be2Si2O8[(OH),O]2 P 21 /a 2/m
09.AJ.20 Hingganite-(Y) Y2([])Be2Si2O8(OH)2 P 21 /a 2/m
09.AJ.20 Melanocerite-(Ce) (Ce,Th,Ca)5(Si,B)3O12(OH,F)•n(H2O)(?) Unk (HEX-R) Trig
09.AJ.20 Minasgeraisite-(Y) CaY2Be2Si2O10 P 21 /a 2/m
Other Gadolinite-(Y) Information
References:
NAME( Ford32) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Ford32)
See Also:
Links to other databases for Gadolinite-(Y) :
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 (UofA)
9 - MinDAT
10 - Mineralienatlas (Deutsch)
11 - Online Mineral Museum
12 - QUT Mineral Atlas
13 - Ruff.Info
14 - WWW-MINCRYST
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Gadolinite-(Y)
Y2Fe++Be2Si2O10
Dana No: 54.02.01b.03 Strunz No: 09.AJ.20
Locality:
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