Iwashiroite-(Y) Mineral Data

General Iwashiroite-(Y) Information

Chemical Formula:

YTaO4

Composition:

Molecular Weight = 313.16 gm

Calcium 0.13 % Ca 0.18 % CaO

Samarium 0.48 % Sm 0.56 % Sm₂O₃

Gadolinium 1.00 % Gd 1.16 % Gd₂O₃

Dysprosium 2.08 % Dy 2.38 % Dy₂O₃

Yttrium 23.00 % Y 29.20 % Y₂O₃

Holmium 0.53 % Ho 0.60 % Ho₂O₃

Erbium 1.60 % Er 1.83 % Er₂O₃

Thulium 0.54 % Tm 0.62 % Tm₂O₃

Lutetium 0.56 % Lu 0.64 % Lu₂O₃

Thorium 0.74 % Th 0.84 % ThO₂

Ytterbium 2.76 % Yb 3.15 % Yb₂O₃

Uranium 0.76 % U 0.86 % UO₂

Tantalum 33.51 % Ta 40.92 % Ta₂O₅

Titanium 0.31 % Ti 0.51 % TiO₂

Niobium 11.57 % Nb 16.55 % Nb₂O₅

Oxygen 20.44 % O

______ ______

100.00 % 100.00 % = TOTAL OXIDE

Empirical Formula:

Y_0.81Yb_0.05Dy_0.04Er_0.03Gd_0.02Lu_0.01Ho_0.01Sm_0.01U_0.01Th_0.01Ca_0.01Tm_0.01Ta_0.58Nb_0.39Ti_0.02O₄

Environment:

Found in the dumps near the no. 1 pit. Suishoyama mine worked several NYF-type pegmatites. Dimorphous with formanite.

IMA Status:

Approved IMA 2003 (Dana # Added)

Locality:

Suishouyama pegmatite, Kawamata town, Fukushima Prefecture, Tohoku Region, Honshu Island, Japan. Link to MinDat.org Location Data.

Name Origin:

Named for the old prefectural name of Fukushima prefecture (Iwashiro).

Synonym:

IMA2003-053

Iwashiroite-(Y) Image

Images:

Iwashiroite-(Y)

Comments: Polished section of an aggregate of minute iwashiroite-(Y) crystals. Some of the aggregates appear dark blue owing to internal reflections.
Location: Suishoyama, Kawamata Town, Fukushima Prefecture, Japan. (Journal of Mineralogical and Petrological Sciences, v101:170). Scale: See Image.
© JMPS

Iwashiroite-(Y) Crystallography

Axial Ratios:

a:b:c =0.9653:1:0.9374

Cell Dimensions:

a = 5.262, b = 5.451, c = 5.11, Z = 2; beta = 95.12° V = 145.99 Den(Calc)= 7.12

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 2/a

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

By Intensity(I/I_o): 3.13(1)(111), 2.95(0.94)(111 ), 1.862(0.29)(022 ),1.89(0.29)(220 ), 2.73(0.26)(020 ), 2.62(0.23)(200 ), 1.614(0.2)(131 ),

Physical Properties of Iwashiroite-(Y)

Cleavage:

{010} Good, {001} Poor

Color:

Amber brown, Brown.

Diaphaneity:

Translucent

Fracture:

Brittle - Subconchoidal - Brittle frature with subconchoidal fragments

Habit:

Platy - Sheet forms (e.g. micas).

Habit:

Striated - Parallel lines on crystal surface or cleavage face.

Hardness:

6 - Orthoclase

Luster:

Vitreous - Adamantine

Streak:

pale brown

Optical Properties of Iwashiroite-(Y)

Optical Data:

NCalc= 2.23 - from Gladstone-Dale relationship (KC = 0.1724) where Ncalc=Dcalc*KC+1

Reflectivity

**Standardized Intensity (100%) Reflection Spectra of Iwashiroite-(Y) in Air**
λ	R₁	R₂	∑ R₁(λ)	∑ R₂(λ)
400 nm	15.30	14.40
470 nm	14.10	13.80
546 nm	13.80	13.60
589 nm	13.90	13.60
650 nm	14.00	13.70
700 nm	14.30	14.10

**Standardized Intensity (100%) Reflection Spectra of Iwashiroite-(Y) in Oil**
λ	R₁	R₂	∑ R₁(λ)	∑ R₂(λ)
400 nm	5.20	5.20
470 nm	4.40	4.10
546 nm	4.50	4.00
589 nm	4.80	4.20
650 nm	5.00	4.60
700 nm	5.90	5.80

**Calculated Relative Intensity Colors of Iwashiroite-(Y) in Air**
Relative Intensity	0%	70%	100%	140%	210%	280%	350%	420%	490%	560%	630%	650%
R₁
R₂

**Calculated Relative Intensity Colors of Iwashiroite-(Y) in Oil**
Relative Intensity	0%	100%	200%	300%	400%	500%	600%	700%	800%	900%	1000%
R₁
R₂

Calculated Properties of Iwashiroite-(Y)

Electron Density:

Bulk Density (Electron Density)=6.21 gm/cc
note: Specific Gravity of Iwashiroite-(Y) =7.12 gm/cc.

Fermion Index:

Fermion Index = 0.03
Boson Index = 0.97

Photoelectric:

PE_{Iwashiroite-(Y)}= 569.82 barns/electron
U=PE_{Iwashiroite-(Y)} x r_electron=3,537.63 barns/cc.

Radioactivity:

GRapi = 70,311.67 (Gamma Ray American Petroleum Institute Units)
Concentration of Iwashiroite-(Y) per GRapi unit = 14.22 (PPM)

Iwashiroite-(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) 432.60 ±108.15 grams of pure Iwashiroite-(Y) .

**Estimated Radioactivity from Iwashiroite-(Y)** - weak
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 / 6.45 cm	1,693,384	4.58E-05	70,311.67	23.12
100 gm / 2.99 cm	169,338	4.58E-06	7,031.17	2.31
10 gm / 1.39 cm	16,934	4.58E-07	703.12	0.23
1 gm / 6.45 mm	1,693	4.58E-08	70.31	0.02
0.1 gm / 2.99 mm	169	4.58E-09	7.03	0.00
0.01 gm / 1.39 mm	17	4.58E-10	0.70	0.00
0.001 gm / 0.64 mm	2	4.58E-11	0.07	0.00

Weight of pure Iwashiroite-(Y) in grams (gm) and Calculated Diameter of a Sphere with a Density of 7.12 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

Iwashiroite-(Y) Classification

Dana Class:

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

(08.01)where A BO4

(08.01.03)Yttroantalalite-Yttrocolumbite Series

08.01.03.01 Yttrotantalite-(Y) (Y,U,Fe)(Ta,Nb)O4 I2/a 2/m

08.01.03.02 Yttrocolumbite-(Y) (Y,U,Fe)(Nb,Ta)O4 Unk Ortho

08.01.03.03 Iwashiroite-(Y)! YTaO4 P 2/a 2/m

Strunz Class:

07.GA.10 07 - SULFATES (SELENATES, TELLURATES)

07.G - Molybdates, Wolframates and Niobates

07.GA -Without additional anions or H2O

07.GA.10 Formanite-(Y) YTaO4 I 4₁/a 4/m

07.GA.10 Iwashiroite-(Y)! YTaO4 P 2/a 2/m

Other Iwashiroite-(Y) Information

References:

NAME( AmMin, v91, p1946) PHYS. PROP.(AmMin, v91, p1946) OPTIC PROP.(AmMin, v91, p1946)

See Also:

Links to other databases for Iwashiroite-(Y) :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - GeoScienceWorld
4 - Google Images
5 - Google Scholar
6 - MinDAT
7 - Mineralienatlas (Deutsch)
8 - Online Mineral Museum
9 - QUT Mineral Atlas
10 - Ruff.Info

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

Iwashiroite-(Y)

YTaO4
Dana No: 08.01.03.03 Strunz No: 07.GA.10
Locality:

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