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Kobeite-(Y) Mineral Data

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General Kobeite-(Y) Information

Help on Chemical  Formula: Chemical Formula: (Y,U)(Ti,Nb)2(O,OH)6 (?)
Help on Composition: Composition: Molecular Weight = 319.10 gm
   Yttrium   25.08 %  Y    31.84 % Y2O3
   Uranium    7.46 %  U     8.46 % UO2
   Titanium  22.51 %  Ti   37.55 % TiO2
   Niobium   14.56 %  Nb   20.83 % Nb2O5
   Hydrogen   0.32 %  H     2.82 % H2O
   Oxygen    30.08 %  O
            ______        ______ 
            100.00 %      101.50 % = TOTAL OXIDE
Help on Empirical Formula: Empirical Formula: Y0.9U0.1Ti1.5Nb0.5O5(OH)
Help on Environment: Environment: In granite pegmatites.
Help on IMA Status: IMA Status: Valid Species (Pre-IMA) 1950
Help on Locality: Locality: Kobe-Mura [presently Oyama-cho], Japan. Link to MinDat.org Location Data.
Help on Name Origin: Name Origin: Named for the locality.
Help on Name Pronunciation: Name Pronunciation: Kobeite-(Y) Say KOBEITE-(Y)

Kobeite-(Y) Image

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Comments: Subparallel aggregate of black, tabular, euhedral kobeite-(Y) crystals in matrix.
Location: Ohro, Kobe, Kyoto, Japan. Scale: Picture size 5 mm.
© Paul M. Schumacher

Kobeite-(Y) Crystallography

Help on Cell Dimensions: Cell Dimensions: a = 5.021, Z = 1; V = 126.58 Den(Calc)= 4.19
Help on Crystal System: Crystal System: Isometric Space Group: Cubic
Help on X Ray Diffraction: X Ray Diffraction: By Intensity(I/Io): 2.89(1), 1.776(0.8), 1.514(0.7),

Physical Properties of Kobeite-(Y)

Help on Cleavage: Cleavage: None
Help on Color: Color: Brown, Brownish black, Dark brown, Black.
Help on Density: Density: 4.6
Help on Diaphaneity: Diaphaneity: Transparent to Translucent
Help on Fracture: Fracture: Brittle - Conchoidal - Very brittle fracture producing small, conchoidal fragments.
Help on Habit: Habit: Metamict - Mineral originally crystalline, now amorphous due to radiation damage.
Help on Habit: Habit: Prismatic - Crystals Shaped like Slender Prisms (e.g. tourmaline).
Help on Habit: Habit: Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite)
Help on Hardness: Hardness: 5.5 - Knife Blade
Help on Luster: Luster: Vitreous - Resinous
Help on Streak: Streak: reddish brown

Optical Properties of Kobeite-(Y)

Help on Gladstone-Dale: Gladstone-Dale: CI meas= 0.049 (Good) - where the CI = (1-KPDmeas/KC)
CI calc= -0.044 (Good) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2876,KPDmeas= 0.262,KC= 0.2756
Ncalc = 2.15 - 2.27
Help on Optical Data: Optical Data: Isotropic, n=2.205.

Calculated Properties of Kobeite-(Y)

Help on Electron Density: Electron Density: Bulk Density (Electron Density)=3.86 gm/cc
note: Specific Gravity of Kobeite-(Y) =4.19 gm/cc.
Help on Fermion Index: Fermion Index: Fermion Index = 0.02
Boson Index = 0.98
Help on Photoelectric: Photoelectric: PEKobeite-(Y) = 242.17 barns/electron
U=PEKobeite-(Y) x relectron= 933.62 barns/cc.
Help on Radioactivity: Radioactivity:

GRapi = 585,029.27 (Gamma Ray American Petroleum Institute Units)
Concentration of Kobeite-(Y) per GRapi unit =1,709.32 (PPB)

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

Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 10 cm box) 51.99 ± 13.00 grams of pure Kobeite-(Y) .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 5199.2 ±1299.8 grams of pure Kobeite-(Y) .

Estimated Radioactivity from Kobeite-(Y) - strong
Curies (Ci)
If Held in Hand
For One Hour
1000 gm / 7.70 cm 13,352,475 3.61E-04 585,029.27 192.34
100 gm / 3.57 cm 1,335,248 3.61E-05 58,502.93 19.23
10 gm / 1.66 cm 133,525 3.61E-06 5,850.29 1.92
1 gm / 7.70 mm 13,352 3.61E-07 585.03 0.19
0.1 gm / 3.57 mm 1,335 3.61E-08 58.50 0.02
0.01 gm / 1.66 mm 134 3.61E-09 5.85 0.00
0.001 gm / 0.77 mm 13 3.61E-10 0.59 0.00

Weight of pure Kobeite-(Y) in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.19 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

Kobeite-(Y) Classification

Help on  Dana Class: Dana Class: (08)Multiple Oxides with Nb, Ta, and Ti
  (08.03)where A (B2O6)
  (08.03.12)Dana Group Kobeite-(Y) (Y,U)(Ti,Nb)2(O,OH)6(?) Cubic Cubic
Help on  Strunz Class: Strunz Class: 04.DG.05 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate
  04.D - Metal:Oxygen = 1:2 and similar
  04.DG -With large (� medium-sized) cations; chains of edge-sharing octahedra
04.DG.05 Fersmite (Ca,Ce,Na)(Nb,Ta,Ti)2(O,OH,F)6 Pcan 2/m 2/m 2/m
04.DG.05 Euxenite-(Y) (Y,Ca,Ce)(Nb,Ta,Ti)2O6 Pcan 2/m 2/m 2/m
04.DG.05 Kobeite-(Y) (Y,U)(Ti,Nb)2(O,OH)6(?) Cubic Cubic
04.DG.05 Loranskite-(Y) (Y,Ce,Ca)ZrTaO6(?) Unk Ortho
04.DG.05 Polycrase-(Y) (Y,Ca,Ce,U,Th)(Ti,Nb,Ta)2O6 Pcan 2/m 2/m 2/m
04.DG.05 Tanteuxenite-(Y) (Y,Ce,Ca)(Ta,Nb,Ti)2(O,OH)6 Pcan 2/m 2/m 2/m
04.DG.05 Uranopolycrase (U,Y)(Ti,Nb,Ta)2O6 P bcn 2/m 2/m 2/m
04.DG.05 Yttrocrasite-(Y) (Y,Th,Ca,U)(Ti,Fe)2(O,OH)6 Unk Ortho

Other Kobeite-(Y) Information

Help on References: References: NAME( AntBidBlaNic3) PHYS. PROP.(AntBidBlaNic3) OPTIC PROP.(AntBidBlaNic3)
Help on See Also: See Also: Links to other databases for Kobeite-(Y) :
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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Print or Cut-and-Paste your Kobeite-(Y) Specimen Label here :


(Y,U)(Ti,Nb)2(O,OH)6 (?)
Dana No: Strunz No: 04.DG.05





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