Kobeite-(Y) Mineral Data

Kobeite-(Y) Mineral Data +

General Kobeite-(Y) Information

Chemical Formula:

(Y,U)(Ti,Nb)2(O,OH)6 (?)

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

Empirical Formula:

Y_0.9U_0.1Ti_1.5Nb_0.5O₅(OH)

Environment:

In granite pegmatites.

IMA Status:

Valid Species (Pre-IMA) 1950

Locality:

Kobe-Mura [presently Oyama-cho], Japan. Link to MinDat.org Location Data.

Name Origin:

Named for the locality.

Kobeite-(Y) Image

Images:

Kobeite-(Y)

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

Cell Dimensions:

a = 5.021, Z = 1; V = 126.58 Den(Calc)= 4.19

Crystal System:

IsometricSpace Group: Cubic

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

By Intensity(I/I_o): 2.89(1), 1.776(0.8), 1.514(0.7),

Physical Properties of Kobeite-(Y)

Cleavage:

None

Color:

Brown, Brownish black, Dark brown, Black.

Density:

4.6

Diaphaniety:

Transparent to Translucent

Fracture:

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

Habit:

Metamict - Mineral originally crystalline, now amorphous due to radiation damage.

Habit:

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

Habit:

Radial - Crystals radiate from a center without producing stellar forms (e.g. stibnite)

Hardness:

5.5 - Knife Blade

Luster:

Vitreous - Resinous

Streak:

reddish brown

Optical Properties of Kobeite-(Y)

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

Optical Data:

Isotropic, n=2.205.

Calculated Properties of Kobeite-(Y)

Electron Density:

r_electron=3.86 gm/cc
note: r_Kobeite-(Y)=4.19 gm/cc.

Fermion Index

Fermion Index = 0.02978
Boson Index = 0.97022

Photoelectric:

PE_Kobeite-(Y)= 242.17 barns/electron
U=PE_Kobeite-(Y) x r_electron= 933.62 barns/cc.

Radioactivity:

GRapi = 585,028.87 (Gamma Ray American Petroleum Institute Units)

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
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 / 7.70 cm	13,352,469	3.61E-04	585,028.87	192.34
100 gm / 3.57 cm	1,335,247	3.61E-05	58,502.89	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

Dana Class:

8.3.12.1 (8)Multiple Oxides with Nb, Ta, and Ti

(8.3)where A (B2O6)

(8.3.12)Dana Group

8.3.12.1 Kobeite-(Y) (Y,U)(Ti,Nb)2(O,OH)6(?) Cubic Cubic

Strunz Class:

IV/D.20-20 IV - Oxides

IV/D - Oxides with metal : oxygen = 1:2 (MO2 and related compounds)

IV/D.20 - Kassite - Lucasite-(Ce) series

IV/D.20-10 Kassite CaTi2O4(OH)2 P 2₁/a 2/m

IV/D.20-20 Kobeite-(Y) (Y,U)(Ti,Nb)2(O,OH)6(?) Cubic Cubic

IV/D.20-30 Lucasite-(Ce) CeTi2(O,OH)6 I2/a 2/m

Other Kobeite-(Y) Information

References:

NAME( AntBidBlaNic3) PHYS. PROP.(AntBidBlaNic3) OPTIC PROP.(AntBidBlaNic3)

See Also:

Links to other databases for Kobeite-(Y) :
1 -Am. Min. Crystal Structure Database 2 -Athena 3 - EUROmin Project 4 -Google Images 5 -Google Scholar 6 -Handbook of Mineralogy (UofA) 7 -MinDAT 8 -MinMax(Deutsch) 9 -MinMax(English) 10 -Mineralienatlas (Deutsch) 11 -QUT Mineral Atlas

Search for Kobeite-(Y) using:

[ALTAVISTA] [AOL] [About.com] [All-The-Web] [HotBot] [Ixquick] [LookSmart] [MAMMA] [MSN.COM] [Netscape] [Teoma] [Wikipedia] [YAHOO]

Visit our Advertisers for Kobeite-(Y) :
AA Mineral Specimens
A-Rocks Auction
Adams Minerals
B and L Minerals
Dakota Matrix
Dan Weinrich Fine Minerals
Dan Weinrich Auctions
e-Rocks Auctions
Excalibur Minerals
Exceptional Minerals
Fabre Minerals
Greenside Minerals
John Betts Fine Minerals
Masons Minerals
Mineral News
Mineral of the Month Club
MineralsWeb Fine Minerals
Minernet.it
Rockshop.cz Kalat Fine Minerals
T G Fine Minerals
Wrights Rock Shop

Translate Kobeite-(Y) Mineral Data :

Ask about Kobeite-(Y) here :
Ask-A-Mineralogist from the Mineralogical Society of America
Mindat.org's Discussion Groups
Original Rockhounds Discussion Group
Rockhounds Discussion Group on Yahoo Groups
Mineral Discussion Forum from Fabre Minerals - also available in Español

Print or Cut-and-Paste your Kobeite-(Y) Specimen Label here :

Kobeite-(Y)

(Y,U)(Ti,Nb)2(O,OH)6 (?)
Dana No: 8.3.12.1 Strunz No: IV/D.20-20
Locality:

Notes: