Fersmite Mineral Data

General Fersmite Information

Chemical Formula:

(Ca,Ce,Na)(Nb,Ta,Ti)2(O,OH,F)6

Composition:

Molecular Weight = 390.96 gm

Sodium 0.59 % Na 0.79 % Na₂O

Calcium 7.18 % Ca 10.04 % CaO

Cerium 7.17 % Ce 8.40 % Ce₂O₃

Yttrium 2.27 % Y 2.89 % Y₂O₃

Thorium 2.97 % Th 3.38 % ThO₂

Tantalum 13.89 % Ta 16.95 % Ta₂O₅

Titanium 0.24 % Ti 0.41 % TiO₂

Niobium 40.40 % Nb 57.79 % Nb₂O₅

Hydrogen 0.26 % H 2.30 % H₂O

Oxygen 24.55 % O

Fluorine 0.49 % F 0.49 % F

- % F -0.20 % -O=F₂

______ ______

100.00 % 103.23 % = TOTAL OXIDE

Empirical Formula:

Ca_0.7Ce_0.2Y_0.1Na_0.1Th_0.05Nb_1.7Ta_0.3Ti_0.02O₅(OH)F_0.1

Environment:

Accessory mineral in nepheline syenites and carbonatites.

IMA Status:

Valid Species (Pre-IMA) 1946

Locality:

Lake Buldym, Vishnevy-Ilmen Mountains, Southern Ural Mountains, Russia. Link to MinDat.org Location Data.

Name Origin:

Named for Aleksandr Evgenevich Fersman (1883-1945), eminent Russian mineralogist, geochemist, and gemologist.

Name Pronunciation:

Fersmite

Synonym:

ICSD 77474

PDF 39-1392

Fersmite Image

Images:

Fersmite

Comments: Brown prismatic crystal of fersmite in matrix.
Location: Alpe Rosso, Vigezzo valley, Novara, Piedmont, Italy. Scale: Picture size 1.7 mm.
© Thomas Witzke / Abraxas-Verlag

Fersmite Crystallography

Axial Ratios:

a:b:c =0.3835:1:0.3501

Cell Dimensions:

a = 5.718, b = 14.91, c = 5.221, Z = 2; V = 445.12 Den(Calc)= 2.92

Crystal System:

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

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

By Intensity(I/I_o): 3.049(1), 3.762(0.21), 1.527(0.15),

Physical Properties of Fersmite

Cleavage:

None

Color:

Brownish black, Dark brown, Black.

Density:

4.69 - 4.79, Average = 4.74

Diaphaneity:

Subtranslucent to Opaque

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).

Hardness:

4-4.5 - Between Fluorite and Apatite

Luster:

Vitreous - Resinous

Streak:

grayish brown

Optical Properties of Fersmite

Gladstone-Dale:

CI meas= 0.002 (Superior) - where the CI = (1-KPDmeas/KC)
CI calc= -0.62 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.3813,KPDmeas= 0.2349,KC= 0.2354
Ncalc = 1.69 - 2.13

Optical Data:

Biaxial (+), a=2.07, b=2.08, g=2.19, bire=0.1200, 2V(Calc)=36, 2V(Meas)=20-25.

Pleochroism (x):

pale greenish yellow or colorless.

Pleochroism (y):

pale greenish yellow or colorless.

Pleochroism (z):

dark greenish yellow or olive yellow.

Calculated Properties of Fersmite

Electron Density:

Bulk Density (Electron Density)=4.29 gm/cc
note: Specific Gravity of Fersmite =4.74 gm/cc.

Fermion Index:

Fermion Index = 0.0005485184
Boson Index = 0.9994514816

Photoelectric:

PE_Fersmite= 330.35 barns/electron
U=PE_Fersmite x r_electron=1,418.18 barns/cc.

Radioactivity:

GRapi = 57,336.83 (Gamma Ray American Petroleum Institute Units)
Concentration of Fersmite per GRapi unit = 17.44 (PPM)

Fersmite 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) 530.49 ±132.62 grams of pure Fersmite .

**Estimated Radioactivity from Fersmite** - 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 / 7.39 cm	1,329,473	3.59E-05	57,336.83	18.85
100 gm / 3.43 cm	132,947	3.59E-06	5,733.68	1.89
10 gm / 1.59 cm	13,295	3.59E-07	573.37	0.19
1 gm / 7.39 mm	1,329	3.59E-08	57.34	0.02
0.1 gm / 3.43 mm	133	3.59E-09	5.73	0.00
0.01 gm / 1.59 mm	13	3.59E-10	0.57	0.00
0.001 gm / 0.74 mm	1	3.59E-11	0.06	0.00

Weight of pure Fersmite in grams (gm) and Calculated Diameter of a Sphere with a Density of 4.74 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

Fersmite Classification

Dana Class:

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

(08.03)where A (B2O6)

(08.03.03)Dana Group

08.03.03.01 Fersmite (Ca,Ce,Na)(Nb,Ta,Ti)2(O,OH,F)6 Pcan 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 (ï¿½ 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 Fersmite 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 Fersmite :
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 (MinSocAm)
9 - Handbook of Mineralogy (UofA)
10 - MinDAT
11 - Mineralienatlas (Deutsch)
12 - Online Mineral Museum
13 - QUT Mineral Atlas
14 - Ruff.Info
15 - WWW-MINCRYST

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Print or Cut-and-Paste your Fersmite Specimen Label here :

Fersmite

(Ca,Ce,Na)(Nb,Ta,Ti)2(O,OH,F)6
Dana No: 08.03.03.01 Strunz No: 04.DG.05
Locality:

Notes:

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