Samarskite-(Y) Mineral Data

General Samarskite-(Y) Information

Chemical Formula:

(Y,Fe+++,U)(Nb,Ta)5O4

Composition:

Molecular Weight = 299.85 gm

La,Ce,Pr,Nd,Sm, 14.41 % RE 16.81 % REE₂O₃

Yttrium 5.93 % Y 7.53 % Y₂O₃

Uranium 15.88 % U 18.01 % UO₂

Tantalum 12.07 % Ta 14.74 % Ta₂O₅

Niobium 24.79 % Nb 35.46 % Nb₂O₅

Iron 5.59 % Fe 7.99 % Fe₂O₃

Oxygen 21.34 % O

______ ______

100.00 % 100.53 % = TOTAL OXIDE

Empirical Formula:

Y_0.2REE_0.3Fe³⁺_0.3U_0.2Nb_0.8Ta_0.2O₄

Environment:

Accessory mineral in REE-rich granite pegmatites.

IMA Status:

Valid Species (Pre-IMA) 1847

Locality:

Miass, Ilmen Mountains, Southern Ural Mountains, Russia. Link to MinDat.org Location Data.

Name Origin:

Named for Vasilii Yefrafovich von Samarski-Bykhovets (1803-1870), Chief of Staff of the Russian Corps of Mining Engineers.

Name Pronunciation:

Samarskite-(Y) + Pronunciation

Synonym:

Priazovite - mixture of samarskite-(Y) and U,Ti-rich mineral of the pyrochlore group

Samarskite-(Y) Image

Images:

Samarskite-(Y)

Comments: A black crystal of samarskite. Ex collection Gustav Rose 1832, found on his travel together with Alexander von Humboldt through the Ural Mts.
Location: Miass, Ilmen Mts, Chelyabinsk Oblast', Urals Region, Russia. Scale: Crystal size 8 mm.
© Thomas Witzke / Abraxas-Verlag

Images:

Uranpyrochlore Samarskite-(Y)

Comments: Deep greenish-brown resinous crystalline massive uranpyrochlore with black samarskite-(Y).
Location: Beryl Hill, near Yinnietharra Station, Western Australia, Australia. Scale: See Photo.
© Jeff Weissman / Photographic Guide to Mineral Species

Images:

Samarskite-(Y)

Comments: A small but intricate cluster of fairly sharp samarskite-(Y) crystals (overall dimensions 15 by 15 by 22 mm) dug from the floor of the open cut.
Location: Spinelli Quarry (Spinelli prospect), South Glastonbury, Glastonbury, Hartford Co., Connecticut, USA. Scale: See Image.
© Fred Davis

Samarskite-(Y) Crystallography

Axial Ratios:

a:b:c =0.3834:1:0.357

Cell Dimensions:

a = 5.498, b = 14.34, c = 5.12, Z = 4; V = 403.67 Den(Calc)= 4.93

Crystal System:

Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: P bcn

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

By Intensity(I/I_o): 2.98(1), 2.92(0.9), 3.13(0.4),

Forms:

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Forms: ( 1 2 1) ( 1 0 1) ( 2 0 1) ( 0 1 0) ( 1 1 1) ( 1 0 0) ( 0 0 1)

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Physical Properties of Samarskite-(Y)

Cleavage:

{???} Imperfect

Color:

Black, Brownish, Yellowish brown.

Density:

5.6 - 5.8, Average = 5.69

Diaphaneity:

Opaque

Fracture:

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

Habit:

Massive - Uniformly indistinguishable crystals forming large masses.

Hardness:

5-6 - Between Apatite and Orthoclase

Luminescence:

Non-fluorescent.

Luster:

Vitreous - Resinous

Magnetism:

Nonmagnetic

Streak:

reddish brown

Optical Properties of Samarskite-(Y)

Gladstone-Dale:

CI meas= -0.079 (Fair) - where the CI = (1-KPDmeas/KC)
CI calc= -0.247 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.2434,KPDmeas= 0.2105,KC= 0.1952
Ncalc = 1.96 - 2.13

Optical Data:

Isotropic, n=2.2.

Calculated Properties of Samarskite-(Y)

Electron Density:

Bulk Density (Electron Density)=5.01 gm/cc
note: Specific Gravity of Samarskite-(Y) =5.70 gm/cc.

Fermion Index:

Fermion Index = 0.02
Boson Index = 0.98

Photoelectric:

PE_{Samarskite-(Y)}= 694.08 barns/electron
U=PE_{Samarskite-(Y)} x r_electron=3,475.30 barns/cc.

Radioactivity:

GRapi = 1,202,300.20 (Gamma Ray American Petroleum Institute Units)
Concentration of Samarskite-(Y) per GRapi unit = 831.74 (PPB)

Samarskite-(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) 25.30 ± 6.32 grams of pure Samarskite-(Y) .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 2529.9 ±632.47 grams of pure Samarskite-(Y) .

**Estimated Radioactivity from Samarskite-(Y)** - very 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 / 6.95 cm	28,742,552	7.77E-04	1,202,300.20	395.28
100 gm / 3.22 cm	2,874,255	7.77E-05	120,230.02	39.53
10 gm / 1.50 cm	287,426	7.77E-06	12,023.00	3.95
1 gm / 6.95 mm	28,743	7.77E-07	1,202.30	0.40
0.1 gm / 3.22 mm	2,874	7.77E-08	120.23	0.04
0.01 gm / 1.50 mm	287	7.77E-09	12.02	0.00
0.001 gm / 0.69 mm	29	7.77E-10	1.20	0.00

Weight of pure Samarskite-(Y) in grams (gm) and Calculated Diameter of a Sphere with a Density of 5.70 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
Estimated Thorium Activity ( 0.72 % Th) From Sum REE Elements (14.41 % REE)

Samarskite-(Y) Classification

Dana Class:

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

(08.01)where A BO4

(08.01.11)Samarskite Group

08.01.11.01 Samarskite-(Y) (Y,Fe,U)(Nb,Ta)5O4 P bcn 2/m 2/m 2/m

08.01.11.02 Samarskite-(Yb)! (Yb,Y,REE,U,Th,Ca,Fe)(Nb,Ta,Ti)O4 P 2/c 2/m

Strunz Class:

04.DB.25 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.D - Metal:Oxygen = 1:2 and similar

04.DB -With medium-sized cations; chains of edge-sharing octahedra

04.DB.25 Ixiolite (Ta,Nb,Sn,Mn,Fe)O2 P 2/c 2/m

04.DB.25 Ishikawaite (U,Fe,Y,Ca)(Nb,Ta)O4(?) Unk Ortho

04.DB.25 Srilankite (Ti,Zr)O2 P bcn 2/m 2/m 2/m

04.DB.25 Samarskite-(Y) (Y,Fe,U)(Nb,Ta)5O4 P bcn 2/m 2/m 2/m

04.DB.25 Samarskite-(Yb)! (Yb,Y,REE,U,Th,Ca,Fe)(Nb,Ta,Ti)O4 P 2/c 2/m

04.DB.25 Yttrocolumbite-(Y) (Y,U,Fe)(Nb,Ta)O4 Unk Ortho

Other Samarskite-(Y) Information

References:

NAME( AntBidBlaNic3) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

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

Samarskite-(Y)

(Y,Fe+++,U)(Nb,Ta)5O4
Dana No: 08.01.11.01 Strunz No: 04.DB.25
Locality:

Notes:

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