Umohoite Mineral Data

General Umohoite Information

Chemical Formula:

[(UO2)MoO4]•H2O

Composition:

Molecular Weight = 447.98 gm

Uranium 53.13 % U 60.28 % UO₂

Molybdenum 21.42 % Mo 32.13 % MoO₃

Hydrogen 0.45 % H 4.02 % H₂O

Oxygen 25.00 % O

______ ______

100.00 % 96.43 % = TOTAL OXIDE

Empirical Formula:

(UO₂)(MoO₄)•(H₂O)

Environment:

Secondary U and Mo deposits.

IMA Status:

Valid Species (Pre-IMA) 1953

Locality:

Freedom No. 2 mine, Marysvale, Piute County, Utah. Link to MinDat.org Location Data.

Name Origin:

Named for the composition of U, Mo, H.

Name Pronunciation:

Umohoite

Umohoite Image

Images:

Umohoite

Comments: Orange Umohoite aggregates on matrix.
Location: RabÃ©jac, LodÃ¨ve, HÃ©rault, Languedoc-Roussillon, France. Scale: Picture size 1 mm.
© Thomas Witzke / Abraxas-Verlag

Umohoite Crystallography

Axial Ratios:

a:b:c =0.8467:1:1.9429

Cell Dimensions:

a = 6.3748, b = 7.5287, c = 14.628, Z = 4; alpha = 82.64°, beta = 85.95°, gamma = 89.91° V = 694.53 Den(Calc)= 4.28

Crystal System:

Triclinic - Pinacoidal H-M Symbol ( 1) Space Group: P1

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

By Intensity(I/I_o): 4.13(1), 3.2(0.5), 3.15(0.4),

Physical Properties of Umohoite

Cleavage:

None

Color:

Bluish black, Dark green, Black.

Density:

4.55 - 4.93, Average = 4.74

Diaphaneity:

Opaque

Habit:

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

Habit:

Rosette - Bundled tabular aggregates resembling rose flower petals.

Habit:

Tabular - Form dimensions are thin in one direction.

Hardness:

2 - Gypsum

Luster:

Sub Metallic

Streak:

blue gray

Optical Properties of Umohoite

Gladstone-Dale:

CI meas= -0.127 (Poor) - where the CI = (1-KPDmeas/KC)
CI calc= -0.248 (Poor) - where the CI = (1-KPDcalc/KC)
KPDcalc= 0.1874,KPDmeas= 0.1692,KC= 0.1501
Ncalc = 1.64 - 1.74

Optical Data:

Biaxial (-), a=1.66, b=1.831, g=1.915, bire=0.2550, 2V(Calc)=64, 2V(Meas)=65.

Pleochroism (x):

dark blue.

Pleochroism (y):

light blue.

Pleochroism (z):

olive green.

Calculated Properties of Umohoite

Electron Density:

Bulk Density (Electron Density)=4.06 gm/cc
note: Specific Gravity of Umohoite =4.74 gm/cc.

Fermion Index:

Fermion Index = 0.05
Boson Index = 0.95

Photoelectric:

PE_Umohoite=1,444.54 barns/electron
U=PE_Umohoite x r_electron=5,869.21 barns/cc.

Radioactivity:

GRapi = 3,882,185.43 (Gamma Ray American Petroleum Institute Units)
Concentration of Umohoite per GRapi unit = 257.59 (PPB)

Umohoite 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) 7.83 ± 1.96 grams of pure Umohoite .
Estimated Maximum U.S. Postal Shipping Size (10 mRem/hr limit, Unshielded 100 cm box) 783.49 ±195.87 grams of pure Umohoite .

**Estimated Radioactivity from Umohoite** - 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 / 7.39 cm	95,109,420	2.57E-03	3,882,185.43	1,276.33
100 gm / 3.43 cm	9,510,942	2.57E-04	388,218.54	127.63
10 gm / 1.59 cm	951,094	2.57E-05	38,821.85	12.76
1 gm / 7.39 mm	95,109	2.57E-06	3,882.19	1.28
0.1 gm / 3.43 mm	9,511	2.57E-07	388.22	0.13
0.01 gm / 1.59 mm	951	2.57E-08	38.82	0.01
0.001 gm / 0.74 mm	95	2.57E-09	3.88	0.00

Weight of pure Umohoite 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

Umohoite Classification

Dana Class:

49.02.02.01 (49)Basic and Hydrated Molybdates and Tungstates

(49.02)(Hydrated)

(49.02.02)Dana Group

49.02.02.01 Umohoite [(UO2)MoO4]•H2O P1 1

Strunz Class:

04.GC.10 04 - OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodate

04.G - Uranyl Hydroxides

04.GC -With additional cations; with UO2(O,OH)6 hexagonal polyhedra

04.GC.10 Umohoite [(UO2)MoO4]•H2O P1 1

Other Umohoite Information

References:

NAME( Dana8) PHYS. PROP.(AmMin, v 86, p 379) OPTIC PROP.(Dana8)

See Also:

Links to other databases for Umohoite :
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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Print or Cut-and-Paste your Umohoite Specimen Label here :

Umohoite

[(UO2)MoO4]•H2O
Dana No: 49.02.02.01 Strunz No: 04.GC.10
Locality:

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