Yttrocrasite-(Y) Mineral Data

General Yttrocrasite-(Y) Information

Chemical Formula:

(Y,Th,Ca,U)(Ti,Fe+++)2(O,OH)6

Composition:

Molecular Weight = 298.05 gm

Calcium 4.03 % Ca 5.64 % CaO

Yttrium 14.91 % Y 18.94 % Y₂O₃

Thorium 7.79 % Th 8.86 % ThO₂

Uranium 7.99 % U 9.06 % UO₂

Titanium 30.52 % Ti 50.92 % TiO₂

Iron 1.87 % Fe 2.68 % Fe₂O₃

Hydrogen 0.68 % H 6.04 % H₂O

Oxygen 32.21 % O

______ ______

100.00 % 102.15 % = TOTAL OXIDE

Empirical Formula:

Y_0.5Th_0.1Ca_0.3U_0.1Ti_1.9Fe³⁺_0.1O₄(OH)₂

Environment:

Precambrian granites, pegmatites, and metamorphic rocks. A doubtful mineral.

IMA Status:

Valid Species (Pre-IMA) 1906

Locality:

Three miles east of Barringer Hill, Llano Co. in Burnet Co., Texas, USA. Link to MinDat.org Location Data.

Name Origin:

From the Greek for "mixture", because it is a mixture fo yttrium with many other elements.

Name Pronunciation:

Yttrocrasite-(Y) + Pronunciation

Yttrocrasite-(Y) Image

Images:

Yttrocrasite-(Y)

Comments: Polished specimen image showing yellow-orange rhombic sections of prismatic yttrocrasite-(Y) crystals along the fissure in almost black chloritoid aggregate.
Location: Chudnoe Pd-Au deposit, Grubependity lake, Komi Republic, Northern Region, Russia. Scale: Picture Size 4x5 mm.
© Pavel M. Kartashov

Yttrocrasite-(Y) Crystallography

Crystal System:

Orthorhombic Space Group: Unk

Physical Properties of Yttrocrasite-(Y)

Cleavage:

None

Color:

Black.

Density:

4.8

Diaphaneity:

Opaque

Fracture:

Conchoidal - Uneven - Uneven fracture producing small, conchoidal fragments.

Habit:

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

Hardness:

5.5-6 - Knife Blade-Orthoclase

Luminescence:

Radioactive.

Luster:

Resinous

Magnetism:

Nonmagnetic

Streak:

reddish brown

Optical Properties of Yttrocrasite-(Y)

Gladstone-Dale:

CI meas= 0.204 (Poor) - where the CI = (1-KPDmeas/KC)
KPDmeas= 0.2365,KC= 0.297
Ncalc = 2.43

Optical Data:

Isotropic, n=2.12-2.15.

Calculated Properties of Yttrocrasite-(Y)

Electron Density:

Bulk Density (Electron Density)=4.45 gm/cc
note: Specific Gravity of Yttrocrasite-(Y) =4.80 gm/cc.

Fermion Index:

Fermion Index = 0.04
Boson Index = 0.96

Photoelectric:

PE_{Yttrocrasite-(Y)}= 397.50 barns/electron
U=PE_{Yttrocrasite-(Y)} x r_electron=1,768.09 barns/cc.

Radioactivity:

GRapi = 784,723.18 (Gamma Ray American Petroleum Institute Units)
Concentration of Yttrocrasite-(Y) per GRapi unit =1,274.33 (PPB)

Yttrocrasite-(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) 38.76 ± 9.69 grams of pure Yttrocrasite-(Y) .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 3876.1 ±969.03 grams of pure Yttrocrasite-(Y) .

**Estimated Radioactivity from Yttrocrasite-(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 / 7.36 cm	17,782,964	4.81E-04	784,723.18	257.99
100 gm / 3.41 cm	1,778,296	4.81E-05	78,472.32	25.80
10 gm / 1.58 cm	177,830	4.81E-06	7,847.23	2.58
1 gm / 7.36 mm	17,783	4.81E-07	784.72	0.26
0.1 gm / 3.41 mm	1,778	4.81E-08	78.47	0.03
0.01 gm / 1.58 mm	178	4.81E-09	7.85	0.00
0.001 gm / 0.74 mm	18	4.81E-10	0.78	0.00

Weight of pure Yttrocrasite-(Y) in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.80 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

Yttrocrasite-(Y) Classification

Dana Class:

08.03.08.04 (08)Multiple Oxides with Nb, Ta, and Ti

(08.03)where A (B2O6)

(08.03.08)Polycrase Group

08.03.08.01 Polycrase-(Y) (Y,Ca,Ce,U,Th)(Ti,Nb,Ta)2O6 Pcan 2/m 2/m 2/m

08.03.08.02 Euxenite-(Y) (Y,Ca,Ce)(Nb,Ta,Ti)2O6 Pcan 2/m 2/m 2/m

08.03.08.03 Tanteuxenite-(Y) (Y,Ce,Ca)(Ta,Nb,Ti)2(O,OH)6 Pcan 2/m 2/m 2/m

08.03.08.04 Yttrocrasite-(Y) (Y,Th,Ca,U)(Ti,Fe)2(O,OH)6 Unk Ortho

08.03.08.05 Uranopolycrase (U,Y)(Ti,Nb,Ta)2O6 P bcn 2/m 2/m 2/m

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 Yttrocrasite-(Y) Information

References:

NAME( Ford32) PHYS. PROP.(Ford32) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Yttrocrasite-(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 Yttrocrasite-(Y) Specimen Label here :

Yttrocrasite-(Y)

(Y,Th,Ca,U)(Ti,Fe+++)2(O,OH)6
Dana No: 08.03.08.04 Strunz No: 04.DG.05
Locality:

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