Bassetite Mineral Data

General Bassetite Information

Chemical Formula:

Fe++(UO2)2(PO4)2•8(H2O)

Composition:

Molecular Weight = 929.97 gm

Uranium 51.19 % U 58.07 % UO₂

Iron 6.01 % Fe 7.73 % FeO

Phosphorus 6.66 % P 15.26 % P₂O₅

Hydrogen 1.73 % H 15.50 % H₂O

Oxygen 34.41 % O

______ ______

100.00 % 96.56 % = TOTAL OXIDE

Empirical Formula:

Fe²⁺(UO₂)₂(PO₄)₂•8(H₂O)

Environment:

Occurs as a rare secondary mineral in the oxidized zone of some uranium-bearing hydrothermal mineral deposits.

IMA Status:

Valid Species (Pre-IMA) 1915

Locality:

In England, from the Basset group of mines, Illogan, and the South Terras mine, St. Stephen-in-Brannel, Cornwall. Link to MinDat.org Location Data.

Name Origin:

For the Basset mine group, Cornwall, England, from which it was first described.

Name Pronunciation:

Bassetite + Pronunciation

Synonym:

Iron uralite

Kithilite

Bassetite Image

Images:

Bassetite

Comments: Bright yellow, bladed crystals of bassetite.
Location: Capoterra, near Cagliari, Sardinia, Italy. Scale: Size Not Given.
© Lou Perloff / Photo Atlas of Minerals

Bassetite Crystallography

Axial Ratios:

a:b:c =0.4089:1:0.4106

Cell Dimensions:

a = 6.98, b = 17.07, c = 7.01, Z = 2; beta = 90.53° V = 835.20 Den(Calc)= 3.70

Crystal System:

Monoclinic - Prismatic H-M Symbol (2/m) Space Group: P 2₁/m

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

By Intensity(I/I_o): 8.616(1), 2.2162(0.96), 3.4818(0.76),

Physical Properties of Bassetite

Cleavage:

{010} Perfect

Color:

Bronze, Brownish yellow, Greenish brown, Yellow, Olive green.

Density:

3.63

Diaphaneity:

Transparent

Hardness:

2.5 - Finger Nail

Luster:

Vitreous (Glassy)

Streak:

greenish white

Optical Properties of Bassetite

Gladstone-Dale:

CI meas= -0.097 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.076 (Fair) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1649,KPDmeas= 0.168,KC= 0.1532
Ncalc = 1.56 - 1.57

Optical Data:

Biaxial (?), a=1.603, b=1.61, g=1.617, bire=0.0140, 2V(Calc)=88, 2V(Meas)=90.

Calculated Properties of Bassetite

Electron Density:

Bulk Density (Electron Density)=3.31 gm/cc
note: Specific Gravity of Bassetite =3.70 gm/cc.

Fermion Index:

Fermion Index = 0.0051266163
Boson Index = 0.9948733837

Photoelectric:

PE_Bassetite=1,300.50 barns/electron
U=PE_Bassetite x r_electron=4,304.94 barns/cc.

Radioactivity:

GRapi = 3,903,744.05 (Gamma Ray American Petroleum Institute Units)
Concentration of Bassetite per GRapi unit = 256.16 (PPB)

Bassetite 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) 7.79 ± 1.95 grams of pure Bassetite .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 779.17 ±194.79 grams of pure Bassetite .

**Estimated Radioactivity from Bassetite** - 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 / 8.02 cm	91,631,545	2.48E-03	3,903,744.05	1,283.42
100 gm / 3.72 cm	9,163,155	2.48E-04	390,374.40	128.34
10 gm / 1.73 cm	916,315	2.48E-05	39,037.44	12.83
1 gm / 8.02 mm	91,632	2.48E-06	3,903.74	1.28
0.1 gm / 3.72 mm	9,163	2.48E-07	390.37	0.13
0.01 gm / 1.73 mm	916	2.48E-08	39.04	0.01
0.001 gm / 0.80 mm	92	2.48E-09	3.90	0.00

Weight of pure Bassetite in grams (gm) and Calculated Diameter of a Sphere with a Density of 3.70 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

Bassetite Classification

Dana Class:

40.02a.16.01 (40)Hydrated Phosphates, etc

(40.02a)where A++ (B++)2 (XO4) ï¿½ x(H2O), containing (UO2)++

(40.02a.16)Dana Group

40.02a.16.01 Bassetite Fe(UO2)2(PO4)2•8(H2O) P 2₁/m 2/m

40.02a.16.02 Lehnerite Mn[UO2/PO4]2•8(H2O) P 2₁/n 2/m

Strunz Class:

08.EB.10 08 - PHOSPHATES, ARSENATES, VANADATES

08.E - Uranyl Phosphates and Arsenates

08.EB -UO2:RO4 = 1:1

08.EB.10 Bassetite Fe(UO2)2(PO4)2•8(H2O) P 2₁/m 2/m

08.EB.10 Lehnerite Mn[UO2/PO4]2•8(H2O) P 2₁/n 2/m

08.EB.10 Metazeunerite Cu(UO2)2(AsO4)2•8(H2O) P 4/n 4/m

08.EB.10 Meta-autunite Ca(UO2)2(PO4)2•2-6(H2O) P 4/nmm 4/m 2/m 2/m

08.EB.10 Metauranocircite Ba(UO2)2(PO4)2•6-8(H2O) P 2₁ 2

08.EB.10 Metauranospinite Ca(UO2)2(AsO4)2•8(H2O) P 4/nmm 4/m 2/m 2/m

08.EB.10 Metaheinrichite Ba(UO2)2(AsO4)2•8(H2O) P 2₁ 2

08.EB.10 Metakahlerite Fe(UO2)2(AsO4)2•8(H2O) P 4/mmm 4/m 2/m 2/m

08.EB.10 Metakirchheimerite Co(UO2)2(AsO4)2•8(H2O) P 4/mmm 4/m 2/m 2/m

08.EB.10 Metalodevite Zn(UO2)2(AsO4)2•10(H2O) P 4₁/m 4/m

08.EB.10 Metanovacekite Mg(UO2)2(AsO4)2•4-8(H2O) P 4/n 4/m

08.EB.10 Metatorbernite Cu(UO2)2(PO4)2•8(H2O) P 4/n 4/m

08.EB.10 Przhevalskite Pb(UO2)2(PO4)2•4(H2O) Unk Tetra

Other Bassetite Information

References:

NAME( AntBidBlaNic4) PHYS. PROP.(Enc. of Minerals,2nd ed.,1990) OPTIC PROP.(Enc. of Minerals,2nd ed.,1990)

See Also:

Links to other databases for Bassetite :
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 - Uranium Minerals

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Bassetite

Fe++(UO2)2(PO4)2•8(H2O)
Dana No: 40.02a.16.01 Strunz No: 08.EB.10
Locality:

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