Umohoite

{{short description|Uranyl oxide mineral}}

{{infobox mineral

| name = Umohoite

| category = Oxide and Hydroxide

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| image = Umohoite1.jpg

| imagesize = 260px

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| formula = (UO₂)MoO₄·2H₂O

| IMAsymbol = Umo{{Cite journal|last=Warr|first=L.N.|date=2021|title=IMA–CNMNC approved mineral symbols|journal=Mineralogical Magazine|volume=85|issue=3|pages=291–320|doi=10.1180/mgm.2021.43|bibcode=2021MinM...85..291W|s2cid=235729616|doi-access=free}}

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| color = Black, blue-black, dark green, orange-red F. Dal Bo, F. Hatert, S. Philippo (2018). "[https://www.mdpi.com/2075-163X/8/9/414 Supergene Uranyl Mineralization of the Rabejac Deposit, Lodève, France.]" Minerals, Volume 8, Issue 9.

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| system = Triclinic

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| cleavage = Perfect on {001}

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| mohs = 2

| luster = Vitreous

| streak = Blue gray

| diaphaneity = Opaque

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| density = 4.53 - 4.66 g/cm3 (Measured) 4.49(3) g/cm3 (Calculated)

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| refractive = nα = 1.660 nβ = 1.831 nγ = 1.915

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| 2V = Measured: 65°, Calculated: 64°

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| other = 25px Radioactive

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Umohoite is a rare oxide and hydroxide mineral. The name of this mineral reflects its composition: uranyl (U), molybdate (Mo) and water ({{H2O-nl}}). Its chemical formula is (UO₂)MoO₄·2H₂O.{{cite web|url=https://www.mindat.org/min-4093.html|website=mindat.org|title=Umohoite: Umohoite mineral information and data.|access-date=2019-08-14}}

Umohoite's type location is in Marysvale, the mineral was first described by Paul F. Kerr and G. P. Brophy in 1953.Brophy, G.P. & Kerr, P.F. (1953): [http://rruff.info/rruff_1.0/uploads/RME-3046_1953_45-51.pdf Hydrous uranium molybdate in Marysvale ore]. Annual Report June 30, 1952 - April 1, 1953 U.S.Atomic Energy Comm., RME-3046, 45-51.