Lermontovite

 IMA-GP
Uranium 40.4.8.2
(Dana Classification Number)
(No Images) 7/D.43-20
(Strunz ID)

Property Data Remarks
Named for: Mikkail Yur'evich Lermontov (1814 - 1841), Russian poet and writer, who often visited Pyatigorsk, the mineral's type locale, and was killed there in a duel.
Alternate
    Name(s):
  • Lermontovit
  • Lermontovita
    		•   
    Mineral Class:
    Phosphates, Arsenates and Vanadates
      Water-bearing phosphates with unfamiliar anions,
    cations of very large and medium size: Al, Mg and Ca, Na, K
        Vyacheslavite - Lermontovite series
    		 
    Chemical
        Formula:    		 U+4(PO4)(OH) · H2O  
    Chemical
        Composition:
    Hydrogen: (H) 0.82%
    Oxygen: (O) 26.08%
    Phosphorus: (P) 8.42%
    Uranium: (U) 64.68%
    		by weight
    Molecular
        Weight:    		 368.02 daltons (amu)
    Specific
        Radioactivity:

    (All radiation is for a 1 gram, fully aged specimen)

    Specific Activity Dose Rate
    Becquerels Curies milliRems/hour microSieverts/hour
    1.15773 × 1005 3.13 × 10-06 1.56 15.56

    Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
    Crystalography:
    System: Orthorhombic - Dipyramidal
    Axial Ratios: a: 0.5126
    b: 1
    c: 0.5315
    Cell Dimensions: a: 9.74 Å
    b: 19 Å
    c: 10.1 Å
    Z: 12
    V: 1,869.11 Å3
    DenCalc: 3.92
    H-M Symbol: 2/m 2/m 2/m
    Space Group: Ccca
    X-Ray Diffraction:
      By Intensity ( I/Io )    		 (0.):   Å
    (0.):   Å
    (0.):   Å
    		 
    Habit:
  • Massive
  • Spherulites
    		•   
    Cleavage:
    [001]  
    [010]  
    [100]  
    		 
    Fracture: Brittle  
    Moh's
        Hardness:    		    
    Density: 4.5 grams/cm3
    Color: Grey-green  
    Streak: Light green  
    Luster: Silky  
    Diaphaneity:    
    Pleochroism:
    (x):  
    (y:)  
    (z:)  
    		 
    Ultra Violet
        Fluorescence:
    Long Wave:  
    Short Wave:  
    		 
    Magnetism: Non-magnetic  
    Occurance:
  		•  
    Associated
        Minerals:

    Anglesite, Aragonite, Autunite, Azurite, Barite, Bornite, Calcite, Cerussite, Chalcocite, Chalcopyrite, Chrysocolla, Covellite, Cuprite, Dolomite, Galena, Goethite, Halloysite, Hematite, Hemimorphite, Hollandite, Malachite, Marcasite, Nontronite, Opal, 'Psilomelane', Pyrite, Pyromorphite, Quartz var: Amethyst, Safflorite, Siderite, Skutterudite, Sphalerite, Wulfenite

    Mineral   -   > 80% of sites
    Mineral   -   > 60% of sites
    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Lermontovite
    Localities:

    Very rare

    Lermontovite localities
    Notes:

    Strongly radioactive a- and b-particles, g-rays.

    Crystals are probably metamic.