Mindat Logo
Home Page Log In Messageboard The Mindat Directory
Register Search Pages Mineral Chatroom The Mindat Store

Umohoite

This page is currently not sponsored. Click here to sponsor this page.
Big Photo

Rabejac, Lodève, Hérault, Languedoc-Roussillon, France
© Thomas Witzke

Show Umohoite Photos (9)



Formula:
(UO
 
2
)MoO
 
4
 · 2H
 
2
O
System:TriclinicColour:Black, blue-black, dark ...
Hardness:2
Name:The name reflects its composition: uranyl (U), molybdate (Mo) and water (H2O).
This page provides mineralogical data about Umohoite.

Classification of Umohoite

IMA status:Valid - first described prior to 1959 (pre-IMA) - "Grandfathered"
Strunz 8th edition ID:6/G.05-20
Nickel-Strunz 10th (pending) edition ID:4.GC.10

4 : OXIDES (Hydroxides, V[5,6] vanadates, arsenites, antimonites, bismuthites, sulfites, selenites, tellurites, iodates)
G : Uranyl Hydroxides
C : With additional cations; with mainly UO2(O,OH)6 hexagonal polyhedra
Dana 8th edition ID:49.2.2.1

49 : HYDRATED MOLYBDATES AND TUNGSTATES
2 : Hydrated Normal Molybdates and Tungstates
Hey's CIM Ref.:27.3.8

27 : Sulphites, Chromates, Molybdates and Tungstates
3 : Molybdates
mindat.org URL:http://www.mindat.org/min-4093.html
Please feel free to link to this page.

Type Occurrence of Umohoite

Type Locality:Freedom No. 2 Mine, Marysvale District (Marysvale Uranium area), Piute Co., Utah, USA
Year of Discovery:1953

Occurrences of Umohoite

Geological Setting:Secondary mineral in sediment hosted uranium deposits in zone above water table.

Physical Properties of Umohoite

Lustre:Vitreous
Diaphaneity (Transparency):Opaque
Colour:Black, blue-black, dark green
Hardness (Mohs):2
Cleavage:Perfect
Perfect on {001}
Density (measured):4.53 - 4.66 g/cm3
Density (calculated):4.49(3) g/cm3

Crystallography of Umohoite

Crystal System:Triclinic
Cell Parameters:a = 14.6Å, b = 7.5Å, c = 6.38Å
β = 99.08°
Ratio:a:b:c = 1.947 : 1 : 0.851
Unit Cell Volume:V nan ų (Calculated from Unit Cell)
Z:4
Morphology:Tabular plates, rosettes, massive, disseminated, thin veinlets
Comment:pseudorhombohedral

Optical Data of Umohoite

Type:Biaxial (-)
RI values: nα = 1.660 nβ = 1.831 nγ = 1.915
2V:Measured: 65° , Calculated: 64°
Maximum Birefringence:δ = 0.255

Chart shows birefringence interference colour range (at 30µm thickness) and does not take into account mineral colouration.
Surface Relief:Very High
Dispersion:weak r>v
Pleochroism:Visible
Comments:X= dark blue
Y= pale blue
Z= olive-green

Chemical Properties of Umohoite

Formula:
(UO
 
2
)MoO
 
4
 · 2H
 
2
O
Essential elements:H, Mo, O, U
All elements listed in formula:H, Mo, O, U

Relationship of Umohoite to other Species

Related Minerals - Nickel-Strunz Grouping):

- +
4.GC.05Clarkeite
(Na,Ca,Pb)(UO
 
2
)O(OH) · 0-1H
 
2
O
4.GC.15Spriggite
Pb
 
3
(UO
 
2
)
 
6
O
 
8
(OH)
 
2
 · 3H
 
2
O
Related Minerals - Hey's Index Grouping:

- +
27.3.1Lindgrenite
Cu
 
3
(MoO
 
4
)
 
2
(OH)
 
2
27.3.2Powellite
Ca(MoO
 
4
)
27.3.3Wulfenite
Pb(MoO
 
4
)
27.3.4Koechlinite
Bi
 
2
MoO
 
6
27.3.5Sedovite
U(MoO
 
4
)
 
2
27.3.6Mourite
UMo
 
5
O
 
12
(OH)
 
10
27.3.7Iriginite
(UO
 
2
)Mo
 
2
O
 
7
 · 3H
 
2
O
27.3.9Moluranite
H
 
4
U
4+
 
(UO
 
2
)
 
3
(MoO
 
4
)
 
7
 · 18H
 
2
O
27.3.10Cousinite
MgU
 
2
Mo
 
2
O
 
11
 · 6H
 
2
O
27.3.11Calcurmolite
(Ca,Na)
 
2
(UO
 
2
)
 
3
Mo
 
2
(O,OH)
 
11
 · nH
 
2
O
27.3.12Tengchongite
CaO · 6UO
 
3
 · 2MoO
 
3
 · 12H
 
2
O
27.3.13Kamiokite
Fe
 
2
Mo
 
3
O
 
8
27.3.14Ferrimolybdite
Fe
 
2
(MoO
 
4
)
 
3
 · nH
 
2
O

Other Names for Umohoite

Other Languages:
German:Umohoit
Russian:Умохоит
Spanish:Umohoita

Other Information

Health Warning:No information on health risks for this material has been entered into the database. You should always treat mineral specimens with care.

References for Umohoite

Reference List:

- +
Brophy, G.P. & Kerr, P.F. (1953): Hydrous uranium molybdate in Marysvale ore. Annual Report June 30, 1952 - April 1, 1953 U.S.Atomic Energy Comm., RME-3046, 45-51.

Rocks and Minerals (1953): 28: 480.

American Mineralogist (1957): 42: 657-660.

Makarov, E.S. and Anikina, L.I. (1963) Crystal structure of umohoite [UMoO6(H2O)2]·2H2O. Geochemistry: 14-21.

Krivovichev, S.V. and Burns, P.C. (2000a) Crystal chemistry of uranyl molybdates. I. The structure and formula of umohoite. Canadian Mineralogist: 38: 717-726.

Burns, P.C. (2005) U 6+ minerals and inorganic compounds: insights into an expanded structural hierarchy of crystal structures. Canadian Mineralogist: 43: 1839-1894.

Internet Links for Umohoite

Search Engines:
  • Look for Umohoite on Google
  • Look for Umohoite images on Google
    • External Links:
  • Look for Umohoite on Webmineral
  • Look for Umohoite on Athena Mineralogy
  • Look for Umohoite on Mineralien Atlas
  • Raman and XRD data at RRUFF project
  • American Mineralogist Crystal Structure Database
  • Umohoite details from Handbook of Mineralogy (PDF)
    • Mineral Dealers:
  • Search for Umohoite on Well-Arranged Molecules
  • Search for minerals at Heliodor
  • Mineral Classics - Worldwide Collector Quality Minerals and Gems
  • Buy from David K Joyce minerals
  • Wilensky Fine Minerals
  • High-end worldwide specimens & outstanding customer service
  • rare and unusual minerals mainly crystallized
  • Fine and rare minerals from mintreasure.com
  • Top quality minerals from Kristalle of California
  • Rare and Unusual minerals at Mineralogical Research Company
  • Buy fine minerals and gemstones from Pala International
  • webminerals
    • Jobs:
  • Mining & Geology Jobs

    • Localities for Umohoite

    The map shows a selection of localities that have latitude and longitude coordinates recorded. Click on the symbol to view information about a locality. The symbol next to localities in the list can be used to jump to that position on the map.
    Hide Locality List
    (TL) indicates type locality. ? indicates mineral may be doubtful at this locality. All other localities listed without reference should be considered as uncertain and unproven until references can be found.
    Democratic Republic of Congo (Zaïre)
     
    • Katanga (Shaba)
      • Katanga Copper Crescent
        • Shinkolobwe
    		[MinRec 20:286-287]
    France
     
    • Languedoc-Roussillon
      • Hérault
        • Lodève
    		[Le Cahier des Micromonteurs, 1998, 2, p.13-26]
    [MinRec 25:209, 23:433]
    Le Règne Minéral, Hors Série IV (1998)
    Kazakhstan
     
    • Almaty Province (Almaty Oblysy; Almati Oblast')
      • Chu-Ili Mts
    		Can Min 38:717-726; Pekov, I. (1998) Minerals First discovered on the territory of the former Soviet Union 369p. Ocean Pictures, Moscow
    USA
     
    • Arizona
      • Coconino Co.
        • Cameron District
    		No reference listed
    Anthony, J.W., et al (1995), Mineralogy of Arizona, 3rd.ed.: 289, 406; Hamilton, P. & P.F. Kerr (1959), Umohoite from Cameron, AZ, Am.Min.: 44: 1248-1260; Keith (1970), AZ Bur. Mines Bull. 182: 103-159, 202-289; Bollin & Kerr (1958), Guidebook for New Mexico Geol.Soc., 9th. Field Conference F.P. 164-168.
    • New Mexico
      • Guadalupe Co.
    		Minerals of New Mexico 3rd ed.
    • Texas
      • Live Oak Co.
    		R&M 66:3 pp 196-224
    Econ Geol (1986) 81:131-142
    • Utah
      • Piute Co.
        • Antelope Range
          • Henry District (Durkee District)
    		U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
    Page, L. R.; Stocking, H. E.; Smith, H. B. (1956) Contributions to the geology of uranium and thorium by the United States Geological Survey and Atomic Energy Commission for the United Nations International Conference on Peaceful Uses of Atomic Energy, Geneva, Switzerland, 1955. USGS Professional Paper 300 pp97-103
    UGMS Bull 117 Minerals and Mineral Localities of Utah
    Handbook of Mineralogy - Anthony, Bideaux, Bladh, Nichols
      • Sevier Co.
        • Gold Mountain District
    		U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
    • Wyoming
      • Fremont Co.
        • Gas Hills District
    		U.S. Geological Survey, 2005, Mineral Resources Data System: U.S. Geological Survey, Reston, Virginia.
    Can Min 38:717-726
    Mineral and/or Locality
    Search Google
     
    Copyright © Jolyon Ralph and Ida Chau 1993-2012. Site Map. Locality, mineral & photograph data are the copyright of the individuals who submitted them. Further information contact the Site hosted & developed by Jolyon Ralph. Mindat.org is an online information resource dedicated to providing free mineralogical information to all. Mindat relies on the contributions of hundreds of members and supporters. Mindat does not offer minerals for sale. If you would like to add information to improve the quality of our database, then click here to register.
    Current server date and time: 4th Nov 2012 20:32:04
    Mineral and Locality Search
    Mineral:
    and/or Locality:
    Options
    Fade toolbar when not in focusFix toolbar to bottom of page
    Hide Social Media Links
    Slideshow frame delay seconds