Aeschynite-(Nd) Mineral Data

General Aeschynite-(Nd) Information

Chemical Formula:

(Nd,Ce)(Ti,Nb)2(O,OH)6

Composition:

Molecular Weight = 346.61 gm

Cerium 16.17 % Ce 18.94 % Ce₂O₃

Titanium 24.17 % Ti 40.33 % TiO₂

Niobium 6.70 % Nb 9.59 % Nb₂O₅

Hydrogen 0.29 % H 2.60 % H₂O

Neodymium 24.97 % Nd 29.12 % Nd₂O₃

Oxygen 27.70 % O

______ ______

100.00 % 100.58 % = TOTAL OXIDE

Empirical Formula:

Nd_0.6Ce_0.4Ti_1.75Nb_0.25O₅(OH)

IMA Status:

Approved IMA 1982

Locality:

China, Inner Mongolia, Bayan Obo Link to MinDat.org Location Data.

Name Origin:

Named for its composition and from the Greek for "shame," in allusion to the inability of chemists, at the time of its discovery, to separate some of its constituents.

Name Pronunciation:

Aeschynite-(Nd) + Pronunciation

Synonym:

Eschynite

ICSD 23509 (La)

PDF 38-480

Aeschynite-(Nd) Crystallography

Crystal System:

Orthorhombic - Dipyramidal H-M Symbol (2/m 2/m 2/m) Space Group: Pmnb ?

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

By Intensity(I/I_o): 2.93(1), 3(0.9), 1.575(0.7),

Physical Properties of Aeschynite-(Nd)

Cleavage:

None

Color:

Brown.

Density:

4.6 - 5.04, Average = 4.82

Diaphaneity:

Subtranslucent

Fracture:

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

Habit:

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

Habit:

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

Hardness:

5-6 - Between Apatite and Orthoclase

Luster:

Adamantine

Streak:

brown

Optical Properties of Aeschynite-(Nd)

Gladstone-Dale:

CI meas= -0.037 (Excellent) - where the CI = (1-KPDmeas/KC)
KPDmeas= 0.2697,KC= 0.2602
Ncalc = 2.2 - 2.31

Optical Data:

Isotropic, n=2.2-2.4.

Calculated Properties of Aeschynite-(Nd)

Electron Density:

Bulk Density (Electron Density)=4.37 gm/cc
note: Specific Gravity of Aeschynite-(Nd) =4.82 gm/cc.

Fermion Index:

Fermion Index = 0.08
Boson Index = 0.92

Photoelectric:

PE_{Aeschynite-(Nd)}= 241.66 barns/electron
U=PE_{Aeschynite-(Nd)} x r_electron=1,054.85 barns/cc.

Radioactivity:

GRapi = 39,739.70 (Gamma Ray American Petroleum Institute Units)
Concentration of Aeschynite-(Nd) per GRapi unit = 25.16 (PPM)

Aeschynite-(Nd) 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) 765.40 ±191.35 grams of pure Aeschynite-(Nd) .

**Estimated Radioactivity from Aeschynite-(Nd)** - 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 / 7.34 cm	921,499	2.49E-05	39,739.70	13.07
100 gm / 3.41 cm	92,150	2.49E-06	3,973.97	1.31
10 gm / 1.58 cm	9,215	2.49E-07	397.40	0.13
1 gm / 7.34 mm	921	2.49E-08	39.74	0.01
0.1 gm / 3.41 mm	92	2.49E-09	3.97	0.00
0.01 gm / 1.58 mm	9	2.49E-10	0.40	0.00
0.001 gm / 0.73 mm	1	2.49E-11	0.04	0.00

Weight of pure Aeschynite-(Nd) in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.82 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 ( 2.06 % Th) From Sum REE Elements (41.14 % REE)

Aeschynite-(Nd) Classification

Dana Class:

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

(08.03)where A (B2O6)

(08.03.06)Aeschynite group

08.03.06.01 Aeschynite-(Ce) (Ce,Ca,Fe)(Ti,Nb)2(O,OH)6 Pmnb 2/m 2/m 2/m

08.03.06.02 Nioboaeschynite-(Ce) (Ce,Ca)(Nb,Ti)2(O,OH)6 Pbnm 2/m 2/m 2/m

08.03.06.03 Aeschynite-(Y) (Y,Ca,Fe)(Ti,Nb)2(O,OH)6 Pbnm 2/m 2/m 2/m

08.03.06.04 Tantalaeschynite-(Y) (Y,Ce,Ca)(Ta,Ti,Nb)2O6 Pbnm 2/m 2/m 2/m

08.03.06.05 Aeschynite-(Nd) (Nd,Ce)(Ti,Nb)2(O,OH)6 Pmnb ? 2/m 2/m 2/m

08.03.06.06 Nioboaeschynite-(Nd)! (Nd,Ce)(Nb,Ti)2(O,OH)6 Pbnm 2/m 2/m 2/m

08.03.06.07 Nioboaeschynite-(Y)! [(Y,REE),Ca,Th,Fe](Nb,Ti,Ta)2(O,OH)6 Pbnm 2/m 2/m 2/m

Strunz Class:

04.DF.05 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

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

04.DF -With large (ï¿½ medium-sized) cations; dimers and trimers of edge-sharing octahedra

04.DF.05 Aeschynite-(Ce) (Ce,Ca,Fe)(Ti,Nb)2(O,OH)6 Pmnb 2/m 2/m 2/m

04.DF.05 Aeschynite-(Nd) (Nd,Ce)(Ti,Nb)2(O,OH)6 Pmnb ? 2/m 2/m 2/m

04.DF.05 Aeschynite-(Y) (Y,Ca,Fe)(Ti,Nb)2(O,OH)6 Pbnm 2/m 2/m 2/m

04.DF.05 Nioboaeschynite-(Ce) (Ce,Ca)(Nb,Ti)2(O,OH)6 Pbnm 2/m 2/m 2/m

04.DF.05 Nioboaeschynite-(Nd)! (Nd,Ce)(Nb,Ti)2(O,OH)6 Pbnm 2/m 2/m 2/m

04.DF.05 Rynersonite Ca(Ta,Nb)2O6 Pmnb 2/m 2/m 2/m

04.DF.05 Tantalaeschynite-(Y) (Y,Ce,Ca)(Ta,Ti,Nb)2O6 Pbnm 2/m 2/m 2/m

04.DF.05 Vigezzite (Ca,Ce)(Nb,Ta,Ti)2O6 Pmnb 2/m 2/m 2/m

04.DF.05 Nioboaeschynite-(Y)! [(Y,REE),Ca,Th,Fe](Nb,Ti,Ta)2(O,OH)6 Pbnm 2/m 2/m 2/m

Other Aeschynite-(Nd) Information

References:

NAME( Dana8) PHYS. PROP.(Dana) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Aeschynite-(Nd) :
1 - Am. Min. Crystal Structure Database
2 - Athena
3 - EUROmin Project
4 - Ecole des Mines de Paris
5 - GeoScienceWorld
6 - Google Images
7 - Google Scholar
8 - Handbook of Mineralogy (UofA)
9 - MinDAT
10 - Mineralienatlas (Deutsch)
11 - Online Mineral Museum
12 - QUT Mineral Atlas
13 - Ruff.Info
14 - Uranium Minerals

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Aeschynite-(Nd)

(Nd,Ce)(Ti,Nb)2(O,OH)6
Dana No: 08.03.06.05 Strunz No: 04.DF.05
Locality:

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