Plumbomicrolite

 IMA-A 1977-SUB
Uranium 8.2.2.3
(Dana Classification Number)
(Images) 4/C.18-50
(Strunz ID)

Property Data Remarks
Named for: Its Lead content, and its belonging to the microlite group of minerals
Alternate
    Name(s):
  		•  
    Mineral Class:
    Oxides
      Oxides with metal:
      (metal:oxygen = 2:3)
      (M2O3 and related compounds)
        Pyrochlore group
          Microlite series with Ta > Nb
    		 
    Chemical
        Formula:    		 (Pb,Ca,U)2Ta2O6(OH)  
    Chemical
        Composition:
    Calcium: (Ca) 3.02%
    Hydrogen: (H) 0.13%
    Lead: (Pb) 31.27%
    Oxygen: (O) 14.08%
    Tantalum: (Ta) 45.51%
    Uranium: (U) 5.99%
    		by weight
    Molecular
        Weight:    		 795.19 daltons (amu)
    Specific
        Radioactivity:

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

    Specific Activity Dose Rate
    Becquerels Curies milliRems/hour microSieverts/hour
    1.0716 × 1004 2.90 × 10-07 0.14 14.00

    Estimated Average Annual Exposure: 360 mRem (3.6 milliSieverts)
    Crystalography:
    System: Isometric - Hexoctahedral
    Cell Dimensions: a: 10.56 Å
    Z: 6
    V: 1,177.58 Å3
    DenCalc: 6.73
    H-M Symbol: 4/m -3 2/m
    Space Group: Fd3m
    X-Ray Diffraction:
      By Intensity ( I/Io )    		 (1): 1.867 Å
    (0.99): 1.593 Å
    (0.65): 2.642 Å
    		 
    Habit:
  • Euhedral crystals
  • Granular
  • Massive
    		•   
    Cleavage:
    [001]  
    [010]  
    [100]  
    		 
    Fracture:    
    Moh's
        Hardness:    		 5  
    Density: 6.6 grams/cm3
    Color: Orange-yellow  
    Streak: White  
    Luster: Greasy  
    Diaphaneity: Translucent  
    Pleochroism:
    (x):  
    (y:)  
    (z:)  
    		 
    Ultra Violet
        Fluorescence:
    Long Wave:  
    Short Wave:  
    		 
    Magnetism: Non-magnetic  
    Occurance:
  • Lithium-rich pegmatites
  • In alluvium near such pegmatites
    		•   
    Associated
        Minerals:

    Amblygonite, Beryl, Betafite, Cassiterite, Fluorite, 'Gadolinite', 'Garnet Group', Ixiolite, Magnetite, Microcline var: Amazonite, Microlite, 'Monazite', Montebrasite, Pyrochlore, Quartz, Uraninite, Xenotime-(Y), Zircon

    Mineral   -   > 75% of sites
    Mineral   -   > 50% of sites
    Minerals   -   Uranium & Thorium
    mineral links

    		These are minerals known to be found with Plumbomicrolite
    Locations:

    Very rare

    Plumbomicrolite Locations
    Notes:

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

    Crystals are probably metamic.

    Plumbomicrolite Images

    Specimen Top
    (001a) (001b) (001c) (001d)

    Specimen Top
      (001f) (001g)  
       
    Berg Ploskaya, West Keivy Massif, Kola Peninsula, Murmanskaja Oblast', Northern Region, Russia

    Specimen Notes

    Occurrence -  

     

    Crystals -  

     

    Appearence -  

    Diaphaniety -

    Luster -

     

      -  

     

    Specimen Physical Properties
    Size 1.27 cm 1.14 cm 1.14 cm
    Weight: 6.96 grams 21° C. 41% R/H
    g-Radiation Level: 25 cmp 0.025 msieverts background: 23 cpm